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Full text of "Special anatomy and histology: in two volumes (Volume 1)"

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SPECIAL 



ANATOMY 



AND 



HISTOLOGY. 



t 

WILLIAM E. HORNER, M. »., 



PROFESSOR OF ANATOMY IN THE UN1VKRSITY OK PENNSYLVANIA— MfcMBER OF THE IMPERII I. 

MEDICO CHIRURQICAL ACADEMY OF ST. PETERSBCRG— OF THE 

AMERICAN PHILOSOPHICAL SOCIETY, &.C. 



Multuni adhuc restat nperie, multumque restabit, nee ulli nato, post mille saecula 
pracludiiur occasio aliquul adjiciendi. 



SENECA, EPIST. 



IN TWO VOLUMES. 
VOL. I. 

SEVENTH EDITION. 

WITH NUMEROUS ILLUSTRATIONS. 



PHILADELPHIA: 
LEA & BLANCHARD. 



1846. 



v,l_ 



Entered, according to the Act of Congress, for the year 1846, by William 
E. Horner, in the Clerk's Office for the District Court of the Eastern Dis- 
trict of Pennsylvania. 



DEDICATION OF THE SIXTH EDITION. 



TO 

NATHANIEL CHAPMAN, M. D., 

Professor of the Practice of Medicine in the University of Pennsylvania. 

My Dear Sir, 

From the new aspect which it has assumed, I take the 
liberty of dedicating to you the following Treatise on 
Anatomy, heretofore without the patronage of an illus- 
trious name. That this is done in the spirit of disinte- 
rested friendship and esteem, is manifested by the diffe- 
rent paths of professional occupation, that we have fol- 
lowed. I have felt the act as an imperative duty, from 
the efficient encouragement in my early years so copiously 
lavished by yourself; and without which my course of 
life would, in all probability, have been very different, 
and much less satisfactory to myself. That a life ren- 
dered valuable by talents of no common order ; by the 
kindest and most generous of feelings; and so usefully 
employed as yours in mitigating the ills of human ex- 
istence, may be long preserved in its present undimi- 
nished vigour of mind and body is the sincere prayer of 
Your obedient servant and friend, 

W. E. HORNER. 

Philadelphia, Sept. 1st, 1843. 



PREFACE 



TO THE 



SEVENTH EDITION. 



In presenting to the profession a seventh Edition of his 
work on Special Anatomy and Histology, the Author re- 
marks, that it is not a mere re-print of the last edition, 
published three years ago, which itself contained copious 
additions over its predecessors ; but that it has undergone 
several modifications, and many extensions, derived from 
the progressive state of the science of anatomy. Where 
every thing else declares such energy in the cultivation 
of medicine, it was not to be expected that a branch so 
distinguished in modern times by the indefatigable zeal of 
its votaries, should remain stationary ; anatomy accord- 
ingly, though the most settled of all the branches, has not 
been idle during the interval alluded to; but has been en- 
riched by absolutely new and by more perfect observa- 
tions. 

A comparison of the present edition with its ante- 
cedents, will, therefore, the Author hopes, show to the 
student an improved state, in many respects, in regard 
both to Descriptive Anatomy and to Histology: Much of 
the latter especially, having been remodelled and written 
anew since the last edition. 

The present edition has also the advantage of additional 



VI PREFACE. 

illustrations from the best authorities, through numerous 
figures inserted upon its pages : and it is placed in a more 
immediate relation with the volume of Plates, by Dr. 
H. H. Smith, called Anatomical Atlas; they having been 
selected expressly as an elucidation of its text. This con- 
nexion has been done by specific references at the foot of 
the page to the Plates in question. 

That all has been said which belongs to the science of 
Anatomy, no one fully acquainted with the subject will 
admit: but the Author trusts that no well established fact 
of leading importance has been omitted ; and that a suffi- 
cient expansion has been given to the subject to realize 
the principal object, that of furnishing an elementary 
Text Book for the use of students of Medicine. 

Within the reminiscences of the Author some decided 
epochs have occurred in the cultivation of Anatomy. At 
the first appearance of this work, which was in 1826, De- 
scriptive Anatomy, made up almost the whole science, as 
taught in the schools. General Anatomy was known 
but little more than by name in this country; and in our 
parent country had not advanced equally far, in scien- 
tific notice. It was strange almost every where to British 
ears, notwithstanding the sagacity and quickness to im- 
provement of that eminent nation ; and by some of its dis- 
tinguished teachers was professedly derided. Its familiar- 
ity, at present, with both sides of the Atlantic, marks the 
solidity of the basis upon which it is founded, and the 
immense acquisition it has been to pathology and to 
physiology; its actual state has fully justified the promi- 
nent position in which it was placed in my first edition. 
The same deference then felt for this rich and invitincr 
branch of Anatomy, has been retained by me to the pre- 
sent day ; and the subject is again presented vastly im- 
proved in accuracy and augmented in observations, by 
perfections in the construction and application of the 



PREFACE. Vll 

microscope. Among other novelties of decided improve- 
ment in connexion with it may be considered the Synonym 
of Histology, or the doctrine of Texture; which seems to 
mark its boundaries and intentions with a definitiveness, 
palliating largely if not justifying its substitution for the 
original phrase itself of General Anatomy; though now 
sanctioned by half a century nearly of use, and, almost 
consecrated by the choice of Bichat himself. 

If the Anatomy of the period alluded to, had a decided 
impulse beyond that of the preceding century, so the 
Anatomy of the present period may justly claim a well- 
marked and triumphant advance beyond that of 1826: 
organs before unknown, now discovered — arrangements 
of parts formerly in obscurity, now detected — textures not 
long ago of an uncertain and disputable character, now elu- 
cidated and settled The anatomy of the most important 
membranes, as the Mucous, formerly passed over as if there 
were scarcely any descriptive features whatever in them; 
now furnished with a detail — extension — and minuteness 
of observation, leaving the impression, nearly, that there 
is nothing more to be learned about them. Those un- 
tractable and mineral-like bodies, the teeth, exciting once 
almost the doubt of intrinsic organization ; now penetrated 
by the microscope in a wonderful manner, and exhibiting 
the most surprising organization: an organization so cha- 
racteristic and permanent that it has become one of the 
most efficient means of discriminating in fragments of 
animals, the kind to which they belonged, whether of the 
present or of a former order of the world. Each of the 
component parts of the teeth, the cement, enamel and 
ivory, being found to exhibit a specific organization ; its 
fibrils or its tubules, whose arrangement, in being specific, 
gives decided character to the specimen in question. 

Bichat laboured but little with the microscope, too im- 
perfect an instrument at the period of his life, and too 
discrepant in its indications, his slender use of it may be 



Vlll PREFACE. 

considered as marking a profound distrust in it; other- 
wise, with his talents and energy, much more of the 
ground of modern anatomy would have been covered by 
him. He depended principally upon maceration, che- 
mical appliances, and pathological changes. But it is 
now a new instrument, in virtue of its freedom, from the 
imperfections of a former period, and we may here with 
propriety occupy some space in an exposition of its me- 
rits. Invented first by the Dutch or Italians, its improve- 
ments have been slow, both in the mechanical and in the 
optical part. The latter has of course been forced to 
await the precession of new discoveries in the laws of 
Light, and as they have been ascertained and developed, 
the results have been applied to the construction of the 
Microscope. This instrument was not, however, desti- 
tute of interest as far back as nearly two centuries ago; 
for it was in 1674, that by it Hartsoeker discovered the 
existence of animalcules in the spermatic liquor of male 
animals. 

The earlier observers generally used single glasses of 
a lenticular shape, but in a short time followed the inven- 
tion of the compound microscope ; where the image formed 
by the glass nearest the object, became itself the subject 
of a farther magnifying power. For a long time, how- 
ever, the imperfections of both kinds of instruments were 
such as to present the most serious obstacles to correct 
observations, so that every new eye seemed to give a new 
cast to microscopical conclusions. One imperfection 
came from the pencils of light passing confusedly through 
a curved surface of glass, and constituted spherical aber- 
ration: another imperfection arose from the different 
coloured rays of light being transmitted through different 
angles of refrangibility, and constituted chromatic aber- 
ration. These difficulties were to a large degree at length 
surmounted in 1S29, by the invention of Woollaston's 
doublet; since which, improvements have been inces- 



PREFACE. IX 

santly occurring both in the optical and mechanical parts 
of the microscope, in regard to accuracy, power, and ap- 
plicability. 

To appreciate the power of the compound microscope 
of the present period, we are to remember that the human 
eye in good order, but unassisted, sees with difficulty an 
object whose diameter is the hundredth part of a line, 
say the twelve hundredth part of an inch; but the powers 
of the microscope are now so adjusted that the diameter 
of such an object may be multiplied or amplified one, 
two, or more thousands of times; thus making what was 
previously imperceptible, a broad, well -lighted and well- 
defined disc or plane. The consequence of this success- 
ful construction, is that a surface not more than a mil- 
lionth of an inch across, may be satisfactorily examined. 
We may hence infer the applicability of the compound mi- 
croscope in ascertaining the healthy and the diseased con- 
dition of the filaments and molecules of the human body; 
the state of its excretions and secretions; the condition of 
its iluids; and the manner of germinal evolution. 

Of all the fluids of the body, the blood is admitted to 
be the most interesting from its quantity, and from its 
relation to all the great functions of life. Containing as 
it does the source as well as the issues of life, every one 
regards it as no common fluid. At an early period, there- 
fore, the microscope was applied to it and detected, by the 
eyes of Malpighi, numerous rounded granules called 
blood corpuscles. It was for one hundred and sixty 
years debated whether these corpuscles were spherical 
or flat, and for a long time, whether they were solid or 
perforated ; also, their exact size, and the relation of the 
colouring matter to them. In place of all this uncertainty 
the facts now admitted are, that they are minute, disc- 
like cells, containing round or oval nuclei, and having 
incorporated with them the material which gives redness 
to the blood of many animals, though this colour does not 



X PREFACE. 

exist in all. Their nucleated state is not so uniform in 
man as in some other animals, and is supposed to be 
limited to certain stages of their development when it # 
subsequently disappears. These blood corpuscles are 
circular in man, and in all the mammalia, except the 
camel tribe, in which they are elliptical ; all other verte- 
brated animals, including reptiles, birds, and fishes, have 
them elliptical. In man the diameter of these globules 
averages about the iota part of an inch, or ?h of a line, 
some being saW and others ^W of an inch ; but in the 
proteus, where they are elliptical, their length is as much 
as A of a line, or the *h of an inch. In the Napu musk 
deer their diameter descends to the _ T ,ta& part of an inch. 
Omnivorous animals have them larger than carnivorous, 
and these again larger than herbivorous. There is no 
absolute proportion between their size and that of the 
animal to which they belong. Thus, in the elephant 
their diameter is only twice that of man. 

The microscope has also distinguished in the chyle or 
elaborated part of our food, numerous appropriate globules 
of variable size, larger or smaller than those of the blood. 
These corpuscles, when perfect, consist of granules as- 
sembled around a central one. Bodies of this kind are 
found in the lacteals of the mesentery; and bodies nearly 
analogous, called lymph globules, are found in the lym- 
phatic vessels, in different parts of the system. 

It is well known that human fat is in large part fluid, 
and such being the case, the inquiry very naturally arose 
why does not this fluid then gravitate to the legs and feet, 
like water in dropsy? A reply of problematical truth 
was given, that this oil was contained in oil or fat cells 
like those of the juice of an orange; but the parts were 
too fine for positive proof. The latter we have now got 
indisputably from the microscope; the answer first came 
from Malpighi, but it required near two centuries of ob- 
servations to verify it. 



PREFACE. XI 

The cuticle, that important covering of the body, with- 
out which the finest satin would feel harsh and excite 
pain ; and also without which no internal supply of fluids 
could make up the rapid loss from the surface by evapo- 
ration, the cuticle, I say, has its structure presented to us 
in a most interesting light under the new powers of the 
compound microscope. It is first of all a remarkable 
point in minute anatomy, that wherever there is a free 
surface, almost without exception the surface in question, 
is provided with a cuticle, or an analogous structure as the 
epithelium, and which consists of one or more layers 
of primary cells. We hence detect this covering on the 
entire surface of the skin ; of the alimentary canal ; of the 
genito-urinary cavities; upon the secretory ducts; upon 
the free surface of the peritoneum, pleura, pericardium, 
arthrodial membranes, synovial sacs, in the cavities of 
the blood vessels, &c. &c. 

These cuticles or epithelia are all formed of scales, 
which are found to be cells in a state of compression and 
having a nucleus. A pressed lime or lemon will give 
some idea of the mere mechanism alluded to. The mi- 
nuteness of microscopical observation may be understood 
when it is stated, that the nuclei of such cells have been 
ascertained to measure about the ^^ of an inch, and that 
within them there are nucleoli estimated at the diameter 
of the ^7 of an inch. 

Some of the scales or cells are rounded or polygonal, 

others are cylindrical or conoidal, and others again are 

terminated at their free extremities, by a very fine down 

or line of fringe called cilia, whose length is from {-^ to 

v^— of an inch: some observers claim to have seen them 

12.3 00 

as short as about the 5 -^^ of an inch. These cilia have 
during life, and even for some time after death an inces- 
sant motion, sweeping backwards and forwards, and 
whirling around at their freed extremities so as to de- 
scribe the figure of a cone. 



xn PREFACE. 

The Cellular form is the universal primary condition 
of all vegetable and animal matter. It lays the founda- 
tion of every thing, and its traces and modifications may 
be found in every tissue, at every stage of life, from the 
earliest rudimentary to the most perfect condition. To 
Schwann we owe this idea, more prolific in consequences 
and in philosophical inductions than any other in the ca- 
tegory of physiology. It has been applied by Dr. Barry 
to the tracing of the Embryo from the Germinal vesicle 
of Purkinje, to the evolution of all the organs of the body. 
In every instance it would seem from the researches of 
Schwann, Valentin, and others, that organism is first 
seen as a single cell; this cell within its enclosure gives 
birth to others; and from them, in their turn, germinate 
others; and so the process goes on in an endless succes- 
sion till life terminates. 

Nutrition itself appears to consist in an evolution of 
new cells from pre-existing old ones, which becoming 
effete are broken down and carried off. While the cells 
are in a state of active vitality, each set derives from the 
blood the organic compounds most suitable to their na- 
ture ; as the structure of every separate portion of the 
body has a special affinity for some of the particular con- 
stituents of the blood, and not for others. The appropria- 
tion of these constituents constitutes assimilation, but the 
regulating power which directs this appropriation, is one 
of the secrets of vitality, the nature of which we are as 
little likely to know as that of gravitation or cohesion in 
the phenomena of physics. 

It is a remarkable trait in animal organism that a form 
of growth unknown to it in the healthy state, in fact pa- 
rasitic; takes possession of certain parts and by its evolu- 
tion, destroys the matrix upon which it feeds. Thus in 
the terrifying and fatal form of disease, called Cancer, 
which is so apt to assail the glandular textures of the 
human body ; it has been shown by Miiller and others, 



PREFACE. Xlll 

that it consists in the growth of a mass of cells, which 
develope themselves in their successive generations with 
extreme rapidity ; and destroy the surrounding tissues 
both by pressure and by abstracting the blood essential to 
their nutrition. These parasitic agglomerations, have an 
independent power of growth and of reproduction, and 
can be propagated into healthy animals by inoculation. 
It is even said that vegetable organisms have been latterly 
traced in the parasitic state upon the body of animals ; 
so that a true plant has been found having a regular ap- 
paratus of nutrition and of reproduction.* We have it 
announced too by M. M. Andral and Gavarret, that in all 
albuminous fluids, a trivial chemical appliance of a certain 
kind, will develope an infusory vegetable, to be found 
with the aid of the microscope. f 

Colour, it is now ascertained, depends upon the ex- 
istence of a particular class of vesicles, called Pigment 
Cells. From them are derived the black pigment of the 
eye, and that which marks the distinction of races in the 
human family. In these, as in other instances, the pig- 
ment is composed of minute dark granules deposited in 
primary cells. These granules are among the most 
minute formations of the body, and in their longest dia- 
meter measure only ^jj of an inch. 

The nails of the fingers and toes, simple and inorgan- 
ized as they seem to be, are yet found by the same search- 
ing process to be formed from an aggregation and suc- 
cessive growth of cells. 

Muscular tissue has also received a copious elucidation 
from this source of observation. A point is now defini- 
tively settled, that the muscular fibres of the stomach, 
bowels, and other interior organs; are very different in 
their anatomy, from the muscular fibres of the limbs, and 
such generally as are engaged in the larger motions of 

* Carpenter. Human Physiology, Am. Ed., p. 404. 

t Bulletin of Med. Science, by J. Bell, M. D. Sept 1843^ from Gazette Medicale. 

Vol. I.— b 



XIV PREFACE. 

the body. The nerves formerly considered as mere 
strings, are now ascertained to be tubes. These tubes 
are collected into fasciculi making a chord of some magni- 
tude. To superficial observation these tubes or ultimate 
fibres seem to coalesce by reciprocal anastomosis; but it 
is now settled by the microscope, that from the brain and 
spinal marrow to the peripheral or outer termination of 
these tubes, they keep perfectly and exactly distinct from 
each other. But as each nervous fibril has its distinct 
origin at one point of the brain, and its distinct termina- 
tion at the other end upon a muscle or a sentient surface, 
the action of the muscles and the perceptions are better 
regulated and more precise, than they would be under a 
different arrangement. 

With such augmented means of anatomical research, 
the progress of the science has been immense. Contri- 
butions of the most valuable kind have been made in the 
British dominions, in Germany, France, Switzerland, 
and elsewhere. Modes of elucidation by plates, drawings, 
models, and injections have been improved. Cabinets of 
great value have been collected and arranged, in every 
direction. Our own country has felt this salutary im- 
pulse, by advancing in its scientific labours and books, 
increasing its medical schools, multiplying highly in- 
structed teachers of Anatomy, and imparting a more 
finished degree of accomplishment to its medical Gra- 
duates. 

Under the circumstances actually existing therefore in 
the civilized world, there has never been a period more 
propitious to the cultivation of Anatomy ; and to the ac- 
quiring of points of knowledge indispensable, to the scien- 
tific and successful treatment of disease. And it is in 
this view of being useful, that the Author once more sub- 
mits his labours to the profession. 



TABLE OF CONTENTS. 



VOLUME I. 



Page 
Preface, ._„„„__ v 

Reference to Illustrations, ..... xxiii 

Introduction — Histology, ..... xxv 

Chemical Composition, ---.-. xlvii 

Histogeny, ---.... \\ x 



BOOK I.— NATURAL SKELETON. 

PART I.— Skeleton, 73 

Chap. I. — Histology of the Bones, ... 74 

Sect. 1. — Number and Texture of Bones, - - 74 

2. — Composition of Bones, ... 84 

Chap. II. — Sect. — 1. Periosteum, - - - 93 

2.— Medulla, ... 95 

Chap. III. — Osteogeny, ..... 97 

Sect. 1. — Development of Bones, 97 

2. — Growth of Bones, .... 102 

3. — Formation of Callus, ... 107 

PART. II.— Bones, individually, - - - - 109 

Chap. I. — Trunk, - - . . - no 

Sect. 1. — Spine, ..... no 

2. — Development of Spine, ... 121 

3. — Uses of Spine, - - - - . 122 

4. — Ossa Innominata, ... 128 

5. — Pelvis, generally, .... 133 

6. — Development of Pelvis, ... 136 

7. — Mechanism of Pelvis, ... 137 

8.— Thorax, - - - - - 138 

9. — Cartilages of Ribs, .... 144 

10. — Development of Thorax, ... 146 

11.— Mechanism of Thorax, - - - 147 

Chap. II.— Head, - - - . - 152 

Sect. 1. — Cranium, ..... 152 

2. — Individual Bones of Cranium, - - 155 

3.— Face, - - . . - 169 



XVI CONTENTS. 

Page 

Chap. III. — General Considerations on Head, - - 180 

Sect. 1.— Sutures, - - * - - -180 

2. — Diploic Structure of Cranium, - * 187 

3. — Internal Surface of Cranium, - 189 

4. — External Surface of Head, - i92 

5.— Nasal Cavities, - - - - - 196 

6.— Orbits of the Eyes, - . - - 198 

7. — National Peculiarities of Face, - - ■> 200 

8— Development of Foetal Head, - - 208 

Chap. IV.— Os Hyoides, - - - - - 211 

V. — Upper Extremities, .... 212 

Sect. 1.— Shoulder, - - - - - 212 

2.— Arm, .... 217 

3.— Fore Arm, - - - - - 219 

4.— Hand, ..... 223 

5. — Development of Upper Extremities, - - 231 

6. — Mechanism of Upper Extremities, - - 233 
7.— Motions of Shoulder, .... 234 

8. — Motions of Shoulder Joint, - - 236 
9.— Motions of Fore Arm, .... 237 

10. — Motions of Hand, ..... 240 

Chap. VI. — Inferior Extremities, - 243 

Sect. 1. — Thigh Bone, .... 243 

2.— Leg, - - - - - - 246 

3.— Foot, ----- 252 

4. — Development of Inferior Extremities, - - 263 

5. — Standing, ..... 264 

6. — Locomotion, - 270 

PART III. — Articulations, ..... 279 

Chap. I. — Cartilaginous System, .... 279 

Sect. 1. — Accidental Development of Cartilages, - 284 

2. — Perichondrium, - - . . _ 285 

3. — Articular Cartilages, - 285 

Chap. II. — Fibro-Cartilaginous System, ... 286 

III. — Ligamentous or Fibrous Tissue, - - 287 

Sect. 1. — Histology of, - 287 

2. — Ligaments of Joints, - 291 

3. — Synovial Articular Capsules, - 291 

Chap. IV. — Articulation of Lower Jaw, - 294 

V. — Ligaments of Spine, .... 296 

VI. — Ligaments of Pelvis, . - . . 305 



CONTENTS. 



Chap. VII. — Articulations of Thorax, 

VIII. — Articulations of Upper Extremities, 
IX. — Articulations of Lower Extremities, 



XV11 

Page 
309 
313 
329 



BOOK II.— INTEGUMENTS OF THE BODY. 

PART. I.— Histology of Cellular and of Adipose Substance, 348 

Chap. I. — Cellular Substance, .... 348 

II. — Adeps, - - - - - - 356 

PART II.— Dermoid Covering, ... - 360 

Chap. I. — Skin, generally, ..... 360 

Sect. 1.— Cutis Vera, ..... 362 

2. — Rete Mucosum, ..... 365 

3.— Cuticula, - 371 

Chap. II. — Glandular Organs of Skin, - - - 375 

III.— Nails, ..... 382 

IV. — Hairs, ...... 385 



BOOK III.— MUSCLES. 

PART I.— Muscles and Tendons in genera], - - - 391 

Chap. I. — Histology of Muscles, .... 391 

Sect. 1.— Muscles of Animal Life, -• - - - 393 

2. — Organic Life, - - - - 401 

II.— Muscular Motion, ----- 402 

III.— Shape of Voluntary Muscles, 407 

IV.— Tendons, - - - - - - 408 

PART II.— Special Anatomy of Muscles, - - - 410 

Chap. I. — Muscles of Head and Neck, - - - - 410 

Sect. 1. — Muscles of Face, --,..., 410 

2.— Muscles of Neck, ..... 419 

Chap. II.— Muscles of Trunk, 428 
Sect. 1. — Muscles on Front of Thorax, - - - 428 
2. — Muscles and Fascia? of Abdomen, - - 431 
3. — Muscles of Upper and Posterior part of Abdomen, 442 
4. — Muscles on Posterior Face of Trunk, - - 448 
Chap. III. — Of the Fascia? and Muscles of the Upper Extre- 
mities, ----- 459 

Sect. 1. — Fascia?, ------ 459 

2.— Muscles of Shoulder, - - - - 462 

3.— Muscles of Arm, ----- 454 

B* 



XV111 CONTENTS. 

Page 

Sect. 4. — Muscles of Fore-Arm, ■« 

5.— Muscles of Hand, * 478 

Chap. IV.— Of the Fasciae and Muscles of the Lower Extre- 



mities, 



483 



Sect. 1. — Fasciae, .... - 483 

2. -Muscles of Thigh, - 488 

3. — Muscles of Leg, ... - 499 

4— Muscles of Foot, ,-.,-. 506 

BOOK IV. 

Organs of Digestion, - - - - - 513 

PARTI. — Organs of Mastication and Deglutition, - - 515 

Chap. L— Mouth, ...... 515 

II— Teeth, -. . - - 517 

Sect. 1. — Number of Teeth, and Subdivision, - - 517 

2. — Texture and Organization of the Teeth, - 521 

3.— Gums, ...... 527 

4.— Evolution of Teeth, - - - 527 

5. — Dentition, ---,-. 535 

6. — Irregularities in Dentition, ... 540 

Chap. III. — Tongue, --..-. 543 

Sect. 1. — Muscles of Tongue, - 544 

2. — Mucous Covering of Tongue, -. - - 546 

Chap. IV. — Palate, ..... 559 

V. — Glands of Mouth, .... . 553 

Sect. 1. — Muciparous Glands, - 553 

2. — Salivary Glands, - 555 

Chap. VI. — Pharynx and (Esophagus, ... 559 

Sect. 1. — Pharynx, - 559 

2.— (Esophagus, ----- - 562 



VOLUME II 



BOOK IV. 



CONTINUED. 



Page 

PART II. — Organs of Assimilation, ... - 5 

Chap. I. — Prolegomena on Structure of Glands, - - 5 

II. — Abdomen, generally, - - - - 12 

III. — Of the Peritoneum and Serous Membranes, gene- 
rally, ------ 18 

Sect. 1. — Peritoneum, - - - - 18 

2. — Omenta, - - - . - 20 

3. — Histology of Serous Membranes, - - 25 

Chap. IV. — Chylopoietic Viscera, - - - - 31 

Sect. 1. — Stomach, ----- 31 

2. — Intestinal canal, - - . - 37 
3. — Minute Anatomy of the Mucous Coat of the 

Alimentary Canal, - - - - 51 

4.— Histology of Mucous Membranes, - - 64 

Chap. V.— Assistant Chylopoietic Viscera, - - - 67 

Sect. 1. — Liver, ----- 67 

2.— Spleen, .. . . - -80 

3. — Pancreas, gg 

BOOK V. 

Of the Urinary Organs, ----- 89 

BOOK VI. 

Organs of Generation, - 205 

Chap. I. — Male Organs of Generation, - 105 

Sect. 1. — Penis, - 105 

2. — Mucous Glands and Apparatus, - - in 

3. — Testicles, - - . . - 114 

4.— Muscles and Fasciae of Perineum, - - 122 



XX 



CONTENTS. 



Chap. II. — Female organs of Generation, 
Sect. 1.— Vulva, 

2. — Vagina, 

3. — Uterus, and its Appendages, 
Chap. III. — Breasts, - 



Page 
128 
128 
132 
134 
144 



BOOK VII. 

Organs of Respiration, 
Chap. I. — Larynx, 

II.— Trachea and Glands bordering upon it, 
Sect. i. — Trachea, and Bronchia 
2.— Thyroid Gland, 
3._Thymus Gland, 
Chap. III. — Lungs, - 



152 
152 
161 
161 
165 
167 
169 



BOOK VIII. 

Circulatory system, - - - - ■ - 181 

PART I.— Histology of Circulatory System, - - 181 

Chap. I. — General Considerations, - - - - 181 

II.— Arteries, Texture of, - - - - 196 

HI.— Veins, ditto - - 202 

IV.— Blood, ------ 205 

Sect. 1.— Serum, ----- 209 

2.— Fibrin, - - - - - 211 

3.— Red Globules, - - - - - 213 

PART II.— Special Anatomy of Circulatory system, - - 219 

Chap. I. — Heart, and Pericardium, - 219 

II. — Arteries, - - - - - 231 

S ec t. i. — Aorta and the Branches from its curvature, - 231 

2. — Carotids and their Branches, - - 234 

3 — Subclavian and its Branches, - - - 243 

4. — Branches of Descending Thoracic Aorta, - 254 

5. — Branches of Abdominal Aorta, - - 256 

6. — Primitive Iliac Arteries, - - - 263 

7.— Internal Iliac Ditto, - - - 264 

8.— External Iliac Ditto, - - - 269 

Chap. III.— Veins, - - - - - 282 

S ec t. 1. — Veins of Head and Neck, - - - 282 

2.— Veins of Upper Extremities, - . - 291 



CONTENTS. XXI 

Page 

Sect. 3. — Veins of Lower Extremities, - - - 294 

4. — Veins of Abdomen, .... 296 

5. — Vena Portarum, ----- 300 

Chap. IV. — Peculiarities of the Circulatory System in the 

Foetus, - - - - - 303 

Sect. 1. — Peculiarities of Foetus, &c, ... 303 

2. — Peculiarities of Circulation of Foetus, &c, - - 307 

Chap. V. — Histology of Absorbent System, - 307 

VI. — Special Anatomy of Absorbent System, - 321 

Sect. 1. —Absorbents of Head and Neck, - 321 

2. — Absorbents of Upper Extremities, - - 323 

3. — Absorbents of Inferior Extremities, - - 325 

4. — Deep Absorbents of Pelvis, - 327 

5. — Absorbents of Organs of Digestion, * - 329 

6. — Absorbents of Viscera of Thorax, - - 334 

7. — Absorbents of Parietes of Trunk, - - 337 

8. — Thoracic Ducts, ... - 340 



BOOK IX. 

Of the Nervous System, - 343 

PART I.— Histology of the Nervous System, - - - 343 
II. — Special Anatomy of the Central Portion of the Nervous 

System, ------ 357 

Chap. I. — Medulla Spinalis, and its Membranes, - - 357 

Sect. 1. — Membranes of Spinal Marrow, - - - 357 

2.— Medulla Spinalis, ... 360 

3.— Blood Vessels of Medulla Spinalis, - - 367 

Chap. II. — Encephalon, ----- 368 

Sect. 1. — Membranes of Brain, - 369 

2.— Medulla Oblongata, 379 

3. — Protuberantia Annularis, - 383 

4. — Cerebellum, ----- 384 

5.— Cerebrum, - - - - - 387 

6. — Nerves of Encephalon, ... 402 

7. — Arteries of Brain, - - - - - 411 

PART III— Senses, 417 

Chap. I.— Nose, - - - - - - 417 

II.— Eye, ----- 427 

Sect. 1. — Auxiliary parts of Eye, - 428 

2.— Eyeball, ----- 444 



468 
472 
478 
484 
487 
487 



XXU CONTENTS. 

Page 

Chap. III.— Ear, ----- 4 ^ 

Sect. 1.— External Ear, - 
2. — Tympanum, - 
3. — Labyrinth, - 

4. — Nerves, - 

PART IV.— Special Anatomy of Nerves, - 
Chap. I. — Nerves of Encephalon, 
Sect. 1.— Nervus Olfactorius, - 
2. — Nervus Opticus, 

3 —Nervus Motor Oculi, - 488 

4._ Nervus Trochlearis, - - - - 488 

5.— Nervus Motor Externus, - - - 489 

6. — Nervus Trigeminus, - - - 489 

7 —Nervus Facialis, - 4 " 

8. — Nervus Hypoglossus, - 501 

9. — Nervus Accessorius, - 503 

10. — Nervus Glosso-Pharyngeus, - - - 503 

11. — Nervus Pneumogastricus, - 505 

Chap. II. — -Sympathetic Nerve, - - - - 510 

III.— Nerves of Medulla Spinalis, - 521 

Sect. 1. — Upper Nine Spinal Nerves, - - - 522 

2. — Thoracic Spinal Nerves, - 533 

3. — A.bdominal Spinal Nerves, - 535 



ILLUSTRATIONS TO VOL. I. 



Pig. 


Page 


I. 


82 


2. 


82 


3. 


104 


4. 


292 


5. 


358 


6, 


358 


7. 


363 


8. 


364 


9. 


369 


10. 


374 


11. 


374 


12. 


374 


13. 


379 


14. 


387 


15. 


387 


16. 


399 


17. 


516 


18. 


516 


19. 


549 


'20. 


549 



Purkinjean Corpuscles, 
Scale of Lepidosteus, 
Osteophyte from Dura Mater, 
Vessels on Articular Cartilage, 
Areolar and Adipose Tissue, 
Capillaries of Adipose Tissue, 
Nerves of Cutaneous Papillae, 
Capillaries, Do. 

Pigment Cells, . 
Epidermis magnified 350 diameters 
Epithelium of Tongue, 
Pigment Molecules, 
Odoriferous Glands of Axilla, 
Pulp of Hair injected, 
Whisker of Walrus, 
Muscle, Capillaries of, 
Nerves of Lip, 
Capillaries of Lip, 
Capillaries of Papillae Linguales, 
Epithelium, scales of, 



Authorities, 
after Mandl. 

Carpenter. 
Nature. 
Toynbee. 
Berres. 
Berres. 
" Gerber. 
Berres. 
Mandl. 
Mandl. 
Mandl. 
Mandl. 
Nature. 
Hunter. 
Hunter. 
Berres. 
Gerber. 
Berres. 
Berres. 
Henle. 



VOL. II. 



81. 


33 


22. 


36 


23. 


53 


24. 


65 


25. 


65 


26. 


65 


27. 


65 


28. 


77 


S9. 


95. 



Peritoneum, organized pores of, . . Nature. 

Minute Veins of mucous member of stomach, Nature. 

Intestinal Epithelium, . . . Henle. 

Ciliated Epithelial Cells, . . . Henle. 

Ditto, Ditto, . . . Henle. 

Cylindrical Epithelial cells, . . Henle. 

Ditto in group . . Henle. 

Epithelial cells of Liver, . . . Carpenter. 

Kidney, Vessels of, ... Bowman. 



XXIV 



ILLUSTRATION OF PLATES. 



"ig- 


Page 


29. bis 


108 


30. 


148 


31. 


148 


32. 


192 


33. 


174 


33. bis 


. 192 


34. 


192 


35. 


192 


36. 


193 


37. 


193 


38. 


227 


39. 


350 


40. 


447 


41. 


448 


42. 


451 


43. 


459 


44. 


460 


45. 


463 



Helicine Arteries, 

Mammary Gland, secreting epithelial 

cells of, 
Extreme branches of Milk Ducts, 
Villi Intestinal, capillaries of, 
Lung, Capillaries of, 
Mucous Follicles, capillaries of 
Parotid, Capillaries of, 
Nervous Centres, capillaries of, 
Conjunctiva, capillaries of, 
Choroidea, capillaries of, 
Valves of Aorta, 
Gray matter of Ganglia, 
Epithelial scales of Cornea 
Blood-vessels of Cornea, 
Pigment cells of Choroidea, 
Capillaries of Retina, 
Retina, . 
Lens, 



Authorities, 
after Miiller. 

Lebert. 

Cooper. 

Berres. 

Carpenter. 

Berres. 

Berres. 

Berres. 

Berres. 

Berres. 

Original. 

Valentin. 

Gerber. 

Toynbee. 

Gerber. 

Berres. 

Treviranus. 

Brewster. 



INTRODUCTION. 



CHAPTER I. 



HISTOLOGY OR GENERAL ORGANIZATION OF THE 
HUMAN BODY. 

In passing the eye over the structure of the human 
body it is evident that the latter is formed by an aggre- 
gation of organs and of textures; each adapted to some 
particular function of a vital or of a mechanical kind ; the 
apparatus of the two functions, vital and mechanical, 
being in many instances blended. Some of the organs 
are of a character so peculiar that their texture is repeated 
no where else; other organs have their texture exactly 
renewed in numerous places; a good example of which 
is seen in the muscles, where, from the necessity of mo- 
tion, muscular structure exists at many points, both for 
locomotion and for the internal operations of the body. 
Anatomy as a science has for its object to pourtray all 
these component parts of the body, both solid and fluid, 
under whatever circumstances they may be presented. 

The application of the science to the search of the 
same texture in different organs, and wherever it may 
indeed be found; the tracing of its degree of extension 
and its modifications under all circumstances; in fine, 
a general comparison of it, one parcel with another, 

Vol. I.— c 



XXVI HISTOLOGY. 

constitutes what is called General Anatomy, or His- 
tology.* Each individual texture being in technical 
language called a tissue. 

Special or Descriptive Anatomy, in distinction from 
Histology, teaches the exterior form of organs, their mag- 
nitude, their position, their connexions with adjacent 
parts; and their intimate texture or organization. As in 
this way every individual part is brought under a strict 
review, it is the knowledge of this portion of the science 
which gives skill to the surgeon. 

General Anatomy may be explained, as its great 
founder, Bichat, himself has done it, by the following 
comparison. Chemistry has its simple bodies, as heat, 
light, hydrogen, oxygen, nitrogen, carbon, and so on, 
whose several combinations form all the composite bo- 
dies on the face of the globe. In the same way anatomy 
has its simple tissues, whose varied combinations form 
all the organs of the human body and of animals. These 
tissues are, 

1. The Cellular, .... y^ i p< 348 

2. The Adipose, or Medullary, - 356 

f Arterial, - II. p . 196 

3. VascularJ ^ eno f ' fc 202 

] Lxhalant, - 193 

(^Inhalent, or Absorbent, - 312 

4. Nervous $ AmmalLife ' ' " ^ 

C Organic Life, ■- 347 

5. Osseous, - -- - - . - I. p. 73 

6. Fibrous, or Desmoid, - 287 

7. Cartilaginous, - 279 

8. The Fibro-Cartilaginous, - o§g 

9. Muscular \ ^ nimal Life ' " - 393 

C Organic Life, - - •_ 401 

* From ivm texture, and \oyot word, doctrine of texture. 







TISSUES. 


XXV1L 


10. 


Erectile, or Spongy, as Penis, 


- Vol. II. p. 107 


11. 


Mucous, 


_ 


51-61 


12. 


Serous, 


_ 


25 


13. 


Synovial, 


. 


Vol. I. 291 


14. 


Cutaneous, 


_ 


- 360 


15. 


Epidermic, - 


_ 


371 


16. 


Pilous, - 


_ 


385 


17. 


Corneous, 


_ 


382 


18. 


Glandular, 


- 


- II. p. 5 



Bichat admits twenty-one elementary tissues, but seve 
ral of them are but modifications of one and the same. 
For example, the arterial, the venous, exhalant and inha- 
lent, belong all to the vascular, and I have thought it 
useful to concentrate them under one head ; and so of 
some others. As the intention of the work did not admit 
of the consecutive description of these tissues, reference is 
made to the pages on which they are discussed. With 
this guide they may be studied in immediate succession, 
by the person desirous of a connected outline of His- 
tology, or General Anatomy. 

Many other modes of classification have been proposed 
since Bichat's, they have for the most part been received 
by the profession with indifference, as not furnishing suffi- 
cient inducements for a change. That of Bichat origi- 
nating with himself has become so completely identified 
with the ordinary language of anatomy and pathology, 
that it is by no means probable that it can be supplanted 
by any other. Among the most modern* of the sugges- 
tions of change are those of Schwann, who proposes a 
classification of tissues upon the basis of their cellular 
histogeny. Valentin and Gerber have also made efforts 
at a new system, and have had no better success than 
their predecessors.* Some subdivisions and additions 
have, it is true, been made with advantage under the im- 

* See Encyclop. Anat. vol. vi. p. 131. Paris, 1843. 



XXV11L HISTOLOGY. 

# 

proved application of the microscope, but no general re- 
newal can take place at present upon existing grounds of 
information. 

The distinctions of tissue do not rest upon an imagi- 
nary basis, but have nature for their foundation. The 
organization of each has well marked and characteristic 
peculiarities, which may be ascertained by their diseases, 
and by the influence of different agents, as heat, air, wa- 
ter, acids, alkalis, neutral salts, and putrefaction. Each 
tissue has its particular strength, and its particular mode 
of sensibility, upon which repose all its vital phenomena, 
and the blood is but a common reservoir, where each 
chooses what is in relation to itself. An example how- 
ever, will serve better for illustrating these several points. 
The stomach is composed of four laminae, one is serous, 
another muscular, a third cellular, and a fourth mucous. 
Each of these laminae has its appropriate sensibilities and 
mode of life, which may cause it to be diseased, while all 
the others are healthy. Peritoneal inflammation may 
invade the first, the cramps of colic the second or mus- 
cular, the infiltration of dropsy the third or cellular, and 
dyspepsia the fourth or mucous. 

The several tissues may, therefore, be considered as 
animal matters endowed, each with its own especial 
vital force and physical properties, from the union of 
which results the especial physiological action of the part 
under consideration. 

It thus happens, that the diversity of the tissue of an 
affected organ modifies the symptoms of its diseases, and 
particularly their duration. Hence, nothing is more vague 
in medicine, in regard to duration, than the terms chronic 
and acute. An inflammation in one tissue will go na- 
turally through its stages in a few days, as, for example, 
in the skin, cellular substance, mucous membranes; 
while in the bones and ligaments, on a natural progress 



SOLIDS AND FLUIDS. XXIX 

being also observed, weeks and months are required for 
its accomplishment. It is evident therefore, that a time 
which is chronic in the first three tissues, is acute in the 
last two. 

A chemical analysis of the body demonstrates only a 
few elementary principles ; and they are varied in their 
combinations by a greater or less proportion of one or the 
other. Calcarious matter, the rfeutral salts, carbon, hy- 
drogen, oxygen, nitrogen, sulphur, iron, wrought up by 
the powers of animalization into gelatine, albumen, and 
fibrine, which again are elaborated into the filamentous 
and laminated tissue, constitute nearly the sum total of 
the results of the experiments of animal chemistry. It 
has yet to find out the laws which give to these ele- 
mentary atoms the condition of blood, and afterwards 
change this blood into muscles, nerves, and other tis- 
sues. 

The whole body is formed of solids and of fluids. The 
former when unravelled, consist of filaments, of laminae, 
and of molecules ; their mechanical division does not ad- 
mit of any greater separation. Many of the laminse are 
arranged into membranes, thus forming hollow viscera, 
for containing either articles of food or the excretions ; 
others surround the different solid viscera and separate 
them from the contiguous parts, Other laminae penetrate 
through the most compact structure, and indeed form the 
nidus in which its atoms or particles are deposited. Many 
of these laminae, consist of several thinner laminae, placed 
together and united by filaments arranged into cells, 
which cells receive the ultimate particles of the whole 
fabric, and constitute its base. The laminse also, by 
being wrought into cylinders, constitute vessels of dif- 
ferent kinds, which are distributed in such number 
through the body, that by far the greater part of its struc- 
ture seems to be formed of them. In regard to the fluids, 
they are extremely abundant in number and in quantity 



XXX HISTOLOGY. 

and are found in the cells of the laminated tissue, and in 
the several vessels. One not accustomed to the process 
would be astonished to see when these fluids evaporate 
by exposure to the air, that nearly all parts of the body, 
except the skeleton, lose from one-half to two-thirds of 
their original bulk, and some parts even more. The se- 
veral solid parts of the body are then literally kept soaked 
during life in the fluids; which have for a principal con- 
stituent, simply water. 

There are some animals whose organization is so sim- 
ple, that they possess only the power of sensation, and of 
motion in one part upon another. This is perhaps the 
lowest degree in which animal life does exist, or possibly 
can exist without a new order of things. These quali- 
ties, sensation and motion, are of necessity combined al- 
ways ; they constitute the first ingredients in the com- 
position of life, both in vegetables, and animals, and by 
being modified in various ways by their application to dif- 
ferent organs, may be traced up to the perfect animal, man. 

Nutrition is the first want of every being, and is one 
of the modes of sensation ; therefore, before any other ap- 
paratus is provided for animal life, means are resorted to, 
to carry it on. Vegetables are fixed to the soil, and are 
furnished with great numbers of porous roots, which by 
spreading in different directions, come in contact with the 
moisture of the ground and by simple absorption conduct 
it as the aliment of the plant. There are many animals 
which have a vegetative life almost as simple as this, and 
are fixed permanently to the spot where they came into ex- 
istence ; others are permitted to change their places of 
abode, and a provision for nourishment by roots would 
not answer; hence comes the necessity of a stomach, or 
reservoir in the interior of the body, into which aliment 
may be introduced and transported along with the ani- 
mal. In many instances this stomach seems to constitute 
the whole animal as in a hydatid : it receives such sim- 



CIRCULATION. XXXI 

pie fluids as compose the medium in which it resides, 
and carries on its digestion, with so little change of the 
alime tary matter, that there seems to be nothing of an 
excrementitious kind, as commonly understood, thrown 
off. These animals are found abundantly in the waters 
of tropical regions, exist sometimes in the brain of man, 
and of sheep; in the uterus, and in almost every part of 
the body. But, again, there are stomachs of a more com- 
plex kind, which have opening into them a great number 
of absorbing orifices, called, in the striking language of 
Boerhaave, " genuine internal roots." These stomachs 
may admit fluids only, or they may be large enough to 
receive considerable masses of solid aliment. In the lat- 
ter case exists the necessity of teeth, or some mechanical 
means of triturating the solid food into such fine pieces, 
as will admit of its being exposed by an extensive surface 
to the action of the stomach. But as much of the mat- 
ter thus carried in is unfit for assimilation, and there may 
be even more of it than is required, an intestinal canal is 
provided, by which it is carried out again. Here then 
commence the phenomena of a true digestion, with all its 
modifications and stages. 

The very simple structure of a plant, and its perma- 
nent locality is attended with a circulation of its juices 
equally simple; which is performed and maintained by 
the capillary attraction of its pores, and by evaporation 
from its higher and more exposed parts. This circula- 
tion is the more rapid as the evaporation becomes greater * 
but the latter may become changed into absorption by 
the humidity of the atmosphere ; and the circulation be 
as a consequence reversed from the branches to the roots. 
But it is evident that such animals as possess extensively 
the powers of locomotion, besides having organs more 
numerous and more complex than the parallel fibrillar of 
vegetables, will frequently find themselves in such con- 
ditions of temperature and locality, that a similar circu- 



XXX11 CIRCULATION. 

lation of the nutritious fluid in them could not be main- 
tained. Hence it is necessary to have more powerful and 
regular agents for carrying on the circulation. They, there- 
fore, are furnished with innumerable blood vessels, called 
arteries and veins; which have a common centre the 
heart, for propelling through them the blood or nutritive 
fluid, to all parts of the system. From the heart being 
furnished with valves, which are all in one direction, the 
blood can flow only in a corresponding course ; thus it is 
forced by the heart into the arteries, and after moistening 
the most minute fibres it is received into the capillary 
extremities of the veins and brought back to the heart, 
where it receives another impulse, and performs again 
the round of the body and so on in succession. This 
phenomenon is called the circulation. When it exists in 
animals, blood is always to be found ; for the most part 
red, but in many species white or transparent. The use 
of the blood in them is to receive from the alimentary 
canal, from the skin and lungs, such matter as has been 
assimilated, and to convey it to every part of the body, 
for the purpose of repairing its waste, or providing for its 
growth. It is at the very extremities of the arteries that 
this deposite occurs, and the blood getting into the veins 
loses its bright vermilion colour, becomes of a modena or 
dark blue, and is no longer fit for the purposes of life till 
some of the principles which it has lost by this passage 
are restored to it. This restoration takes place in the 
lungs, where a sort of combustion is performed by the 
absorption of oxygen. This process is called respiration, 
and it exists in all things that live, under various modifi- 
cations of the apparatus performing it. In man it is per- 
formed in two cellular air bags, which have a heart inde- 
pendent of the one just mentioned, for propellino- the 
blood through the ramifications of their vessels. In fish 
there are gills, which have their surfaces exposed to the 
water, and are aerated by the air contained in the water, 



SENSATION. XXX111 

and the same heart which supplies the general circula- 
tion, also fills a large artery, that is distributed very mi- 
nutely through the gills. But in insects, where there 
are no blood vessels, and the nutritious fluid is contained 
in cells, there are, distributed over their bodies, air tubes, 
which transmit atmospheric influence. 

The blood vessels, in addition to the function of carry- 
ing nutritious matter, perform an essential part of a very 
different character. All the atoms of which the bod} r is 
composed, after residing in it for a time, become no longer 
fit for use; their farther residence is, in fact, injurious, 
and it is necessary to remove them. A system of vessels 
is provided for this purpose, called the absorbents, which 
are the scavengers of the body. Taking up, therefore, 
these effete atoms, they convey them into the blood ves- 
sels, where they are mixed with the common mass of 
blood. Several organs are provided, as the liver, the kid- 
neys, the surface of the body, and the lungs, through 
which these effete particles are discharged from the blood 
in the form of excretions; as the bile, the urine, perspira- 
tion, and pulmonary exhalation. 

We haie now sketched the human machine as far as 
its internal existence, or self-preservation, is concerned in 
the functions of digestion, circulation, respiration, and 
excretion. Let us proceed in the inquiry by a rapid 
glance at those organs by which it is put into a relation 
with surrounding objects, and on which it depends for 
the sublime operations of the understanding. 

Sensation is derived from the nervous system, com- 
posed of the brain, the spinal marrow and the nerves. 
The latter may be traced to many parts of the body, and 
are supposed to be distributed to all. They maintain its 
different sympathies, keep the several organs in one har- 
monious course of action, and, in some instances at least, 
are indispensable to the performance of their functions. In 



XXXIV SENSATIONS. 

addition to these, many of the nerves have at their extre- 
mities organs of a particular construction, each fashioned 
in the best manner for the execution of its office, in 
making us acquainted with exterior objects. The in- 
terior extremities of all these nerves terminate either in 
the brain or spinal marrow ; the external are the points 
intended by nature to be affected by the objects around 
us; but it is indispensable to consciousness, that their 
line of communication with the brain be not interrupted. 
The sense most extended is that of the touch, which is 
enjoyed by all parts of the surface of the body ; the others 
are thought, by very respectable physiologists, to be only 
more exalted modifications of* it, and are susceptible of 
more delicate impressions. It is scarcely necessary to 
mention that the other sensations are executed by the eye, 
the ear, the tongue, and the nose. 

The Sense of Touch is the most important of all, and 
the least liable to error in its reports. To exercise it, it 
is necessary for the 'body, under examination, to come 
into contact with ours : hence, its operations are so me- 
chanical, that but little is left to the imagination, and they, 
therefore, serve to verify and to correct the impressions 
on the other senses, more particularly those on the eye. 
It is the sense of touch by which we learn accurately the 
dimensions of bodies, and the figures of such as are hard. 
The hand, or any other part, by being applied to them 
in various directions, informs us whether they are flat, 
round or angular. A greater or less degree of pressure in- 
forms us whether they are soft or hard, and by rubbino-, 
we ascertain whether they are rough or polished. The 
resistance they make to motion, teaches us whether they 
can or cannot be moved, and their being impelled ao-ainst 
us shows the momentum with which they act, as well as 
its direction. Our ideas of heat and of cold are also de- 
rived from this source. It is not asserted that all parts of 
the surface of the body enjoy equally the sense of touch ; 



SIGHT. XXXV 

on the contrary, this sensibility is more or less active, 
according to the organization of the part, and as its nerves 
are more or less numerous and exposed; hence we find it 
most exquisite and perfect in the ends of the fingers. 
This, therefore, being the most important of the senses 
the magnitude of its influence on the habits and intelli- 
gence of different animals is immense. 

Man, from the nudity and the delicacy of the texture 
of his skin, derives, from this source, a discrimination and 
refinement, in regard to the nature of bodies, much supe- 
rior to what many other animals possess. 

The Sight enables us to distinguish the colour, the 
quantity, and the directions of the rays of light which 
proceed from a luminous body ; or, in other words, to as- 
certain its situation, size, and figure. In each, however, 
of the latter we are exposed to great deception ; for the 
rays of light, by falling on a mirror, or any other plane 
reflecting surface, before they reach the eye, will induce 
us to believe the body to be in that direction. Bodies 
which are near, reflect more rays of light than such as 
are distant: we thus estimate distance by the eye; but it 
happens continually, that some bodies naturally reflect 
more rays than others; in consequence of which a very 
luminous body, at a great distance, will frequently be 
thought to be much nearer to us, than such as are more 
within our reach. Mistakes of this kind can only be 
corrected by the sense of touch, and our habitual refe- 
rence to it, and continued experience, finally enable us to 
form prompt and just decisions. The eye, however, infi- 
nitely exceeds the touch in the rapidity with which it 
communicates ideas, and also, in the extensiveness of its 
application in a single moment. It is, therefore, an or- 
gan of the first utility in making us acquainted with sur- 
rounding objects. Man does not possess it to that great 
perfection that some other animals do; he can neither see 



XXX Vi SENSATIONS, 

as far as the vulture or eagle, nor so minutely as the fly ; 
yet his ingenuity has enabled him to excel both. For, 
with the telescope, he examines worlds in the immensity 
of space, which, under common examination, are either 
invisible, or form mere points in the heavens. And with 
the microscope he sees the texture of the most minute 
object. 

The Ear, along with the powers of articulation, enables 
the whole human family to make common stock of the 
knowledge which each individual may possess. As con- 
nected with the preservation of the individual, it is much 
less important than the eye or the touch : yet, considering 
it as a means by which we receive knowledge and impart 
it to others, the aggregate of human intellect depends for 
its present state and future improvement essentially upon 
it. In its acuteness, we are much inferior to many other 
animals; neither have we, by instruments, been able to 
do much in improving it : yet, by cultivation and by stu- 
dying its most minute and delicate impressions, an end- 
less source of instruction and amusement has been opened 
to us, in the intonations of language, and in the enrap- 
turing strains of harmony. It eminently qualifies man 
for the social state, occasionally warns him of danger, and 
allures him to such things as are useful to his subsist- 
ence. 

In regard to the Taste and to the Smell, they make us 
acquainted only with such objects as are necessary to our 
subsistence. They are enjoyed too imperfectly by man, 
for them to become a fruitful source of his intelligence. 
As they principally lead us to filling the stomach, and to 
debasing the intellectual man into the beast, that eats and 
dies ; the wisdom of nature is as fully demonstrated in the 
imperfection which she has put upon these senses, and in 
our inability to improve them, as in the exalted and va- 



VITAL FUNCTIONS. XXXV11 

ried degrees to which she has carried the others. The 
keenness of the scent of the hound, and the discriminating 
nicety of the bee, in opening sources of enjoyment merely 
physical, would have degraded, instead of elevating us; 
by engrossing our time and ingenuity, in the develop- 
ment of pleasures incompatible with our constitutions and 
destinies. 

Man being thus organized, it is worthy of inquiry in 
what his life consists. According to the celebrated Bi- 
chat, it is " the aggregate of those functions by which 
death is resisted. For such, indeed, is the condition on 
which we live, that every thing surrounding us has a 
tendency to produce our dissolution, by the affinities ex- 
isting between their atoms, and the atoms of which a 
living body is composed. It is plain, therefore, that the 
principle of life, like all other principles in nature, incom- 
prehensible in itself, must be studied by its phenomena.' 1 * 

There are two remarkable modifications of life : one 
is common to the vegetable and to the animal, the other 
is the exclusive attribute of the latter. Under the first 
modification, are included assimilation and excretion, 
which, though exercised under apparently different cir- 
cumstances in animals and in plants, are probably essen- 
tially the same in both. This modification is termed by 
Bichat, Organic Life. By the second modification of life, 
the animal has a more extended sphere of existence than 
the vegetable, is put into a certain relation with all the 
objects that surround him, is made the inhabitant of the 
whole world, and not like the vegetable, confined for ever 
to the place of its birth. By it the animal feels, and is 
conscious of external objects, reflects upon them, moves 
voluntarily, and can communicate, by the voice, his wants 
and apprehensions, his pleasures and his pains. The 

* Rccherches sur la vie et La Mort. 

Vol. I.— d 



XXXV111 VITAL FUNCTIONS. 

functions included under the second modification, are 
termed, by Bichat, Animal Life. 

Each of these lives has two orders of functions, keep- 
ing up its connexion with the objects destined for its ex- 
istence. In animal life, one of these orders may be said 
to commence at the surface of the body, and to be ex- 
tended towards the centre, the impression of exterior ob- 
jects affecting first the senses, then the trunks of nerves, 
and lastly, the brain. A second movement, constituting 
the second order of functions, is afterwards made from 
the centre to the circumference, by which the influence 
of the brain is exercised on the organs of locomotion and 
of voice. These two functions, in animal life, are per- 
fectly equivalent in their operations. He who feels the 
most, will also act the most. Early life is the period of 
quick and multiplied sensations, so is it the period of 
quick and multiplied movements. A partial, or a total 
privation of the sense of sight, causes us to move cau- 
tiously and slowly onwards. The suspension of our 
communication, through sleep, with exterior objects, 
causes also a suspension of the faculties of locomotion 
and of voice. 

In organic life, the first order of functions assimilates 
to the animal the substances which must nourish him, 
and includes digestion, circulation, respiration, and nu- 
trition ; under the influence of which four functions, every 
thing must pass before it can be assimilated. But, after 
a temporary residence, the assimilated particles becoming 
effete and noxious, have to be carried away out of the 
body : by which means the second order of functions in 
organic life is established, consisting of absorption, circu- 
lation, exhalation, and secretion. 

The two functions of organic life differ, however, from 
those of animal life, in not observing, on all occasions, an 
equivalence of action: the diminution of assimilation 
does not involve a corresponding diminution in excre- 



ORGANIC LIFE. XXxix 

tion ; hence, follow emaciation and marasmus, conditions 
in which, assimilation ceasing in part, dis-assimilation is 
exercised to the usual extent, or near it. From this 
sketch, it is seen that the circulation of the blood is the 
connecting link of the two orders of functions in organic 
life, as the brain is the connecting link of the two orders 
of functions in animal life. The blood, is, therefore, in 
fact, composed of two parts or descriptions of matter : 
one is recrementitial, derived from the aliment, and sub- 
servient to the renovation and growth of parts ; the other 
is excrementitial, derived from the wrecks of all our 
organs, and under the necessity of being cast away as 
useless. 

M. Bichat thinks the division of life into Animal and 
Organic, fully warranted by their differing much from 
each other in the exterior shape of their respective or- 
gans, — in their mode of action — in the duration of their 
action, — in the effects of custom or habit upon them, — in 
their relation to the moral part of man, and in their vital 
force. 

One of the most prominent differences in the two lives, 
is the symmetry and duplicity of the Organs of Animal 
Life, and the irregularity in shape of those belonging to 
Organic Life. The impression of Light is received by 
two organs exactly alike. Hearing — Smelling — Touch- 
ing — are likewise performed by organs having their con- 
geners on the opposite sides of the body; and even 
Tasting, though apparently performed by one organ, has 
that organ divided into two equal and symmetrical parts, 
thus making it like the other organs. The w r hole exte- 
rior surface of the body is, indeed, manifestly divided 
into two equal parts, marked off from each other by the 
fissure in the nose, the upper lip, the chin, the raphe of 
the scrotum and perineum, the spinous processes, and the 
depression in the superior posterior part of the neck. 
The Brain and Spinal Marrow, as belonging to animal 
life, consist of two halves, presenting corresponding ar- 



xl 



VITAL FUNCTIONS. 



rangements in the development of cavities and promi- 
nences, and so on, and in sending similar nerves to the 
organs of locomotion and of voice. 

The organs of organic life are marked, on the contrary, 
by the character of striking dissimilitude in their two 
halves, as manifested in the liver, the spleen, the stomach, 
the intestines, the heart, and the great vessels belonging 
to it. There, are, however, some organs of organic life 
in which the difference is less prominent, as the lungs of 
the two sides, the pulmonary arteries, the veins, the 
trachea, the kidneys, the capsular renales, and the sali- 
vary glands. 

From what has been said, we are, perhaps, prepared 
to admit with M. Bichat, that animal life is double ; that 
its phenomena being executed after the same manner on 
both sides of the body, it is very possible for the actions 
of one side to be suspended or destroyed while those of 
the other go on. This, in fact, happens in certain pal- 
sies, where the sensibility and motion of one side are so 
completely suspended, that it resembles a vegetable; all 
relation with exterior objects being cut off, and nothing 
but the function of nutrition being preserved ; whereas 
the other side retains all its animal properties. For 
these reasons Bichat has very quaintly observed that we 
have a right life and a left life. In organic life, on the 
contrary, the functions of the two halves of any organ 
are so allied, that the lesion of one affects the other. 
The liver, in a disease on one side, has its functions im- 
paired throughout : it is the same with the intestinal ca- 
nal, and with the heart. 

Congenital deformities are said to be more frequent in 
the organs of organic life than in those of animal life. 
Several cases have occurred, and Bichat relates one 
which happened in his own amphitheatre, where there 
was a general displacement of the digestive, the circula- 
tory, the respiratory, and the secretory viscera. The 



ORGANIC LIFE. xli 

stomach, the spleen, the sigmoid flexure of the colon, the 
point of the heart, the aorta, and the lung with two lobes, 
were all on the right side. But the liver, the caecum, 
the base of the heart, the venae cavse, the vena azygos, and 
the lung with three lobes were on the left side. All the 
organs placed beneath the middle line, as the mediasti- 
num, the mesentery, the duodenum, the pancreas, the 
division of the trachea, were reversed. I have had occa- 
sion to observe, in our own dissecting rooms, two cases of 
the caput coli removed from the right iliac into the left 
iliac region ; the colon was of the common size and length, 
and being confined to the left side of the abdomen, formed 
there a loop, which ascended into the left hypochondriac 
region, and then descended as usual. In these cases, as 
there was no transverse mesocolon, the duodenum had all 
the coats of the other intestines; and was not attached to 
the front of the right kidney and to the spine. One of 
these was an adult female subject of considerable corpu- 
lency, the other a corpulent male. 

Another difference between organic and animal life 
exists in the mode of action of their respective organs. 
Each of the organs of animal life being double, our sen- 
sations are the more exact, as there exists between the 
two impressions, from which they result, a more perfect 
correspondence. We see badly when the images trans- 
mitted to the brain, are derived through eyes of unequal 
strength. Without knowing this law as theorists, we 
instinctively show its influence in shutting one eye while 
looking through a convex glass; whereby we prevent a 
confusion of images arising from two impressions of un- 
equal force, concerning the same body : when one eye is 
weaker than the other, we squint involuntarily, and it 
finally becomes a habit, in order to avoid the confusion 
of perception from two unequal images on the brain. 
This accounts for squinting, both in early life, from some 
congenital cause, and for that squinting which is the 

D* 



Xlii VITAL FUNCTIONS. 

result of inflammation, in more advanced life. A little 
reflection on this head will satisfy us ; for as a single 
judgment or perception is, for the most part, formed from 
the two impressions, one on each eye, how is it possible 
that this judgment can be accurate, when the same body 
is presented at the same moment with vivid or faint 
colours, accordingly as it was painted on the strong or 
the weak eye ? 

The ear is subjected to the same law as the eye. If, 
in the two sensations composing the act of hearing, one 
is received upon an organ better developed than the 
other, and more discriminating in its functions, it will 
leave an impression more clear and distinct; but the 
brain being affected simultaneously by the unequal im- 
pressions, will be the seat of an imperfect conception. 
This case constitutes a false ear in music, and from the 
impressions being continually confused, prevents the 
individuals from judging rightly between harmony and 
dissonance. 

A similar reasoning has been founded by Bichat upon 
the structure of the Nose, Mouth, and Organs of Touch. 
He believes also that the brain itself, as the seat of the 
mind, may become the cause of error in our ideas, when 
the two halves of it are not perfectly alike ; for example, 
if one of the hemispheres be more strongly organized 
than the other, better developed every where, and more 
susceptible of a vivid impression. The brain transmits 
to the soul the impression or impulse derived from the 
senses, as the latter transmit to the brain their impres- 
sions; it is, therefore, to be believed that the soul will 
perceive confusedly, when the hemispheres, beino- une- 
qual in force, do not blend into one, the double impres- 
sion upon them. In proof of this, it is common to see 
mental derangements depending on the compression of a 
hemisphere by effused blood, by pus, by depressed bone, 
and by an exostosis from the internal face of the cranium. 



ORGANIC LIFE. xliii 

Even where every sign of compression is removed, the 
hemisphere occasionally takes a long time to regain its 
action, so as to recover from the alienation. 

This harmony of action exists also in the organs of 
locomotion, and of voice ; and any thing which interrupts 
their symmetry destroys the precision with which their 
functions are executed. 

Opposed to this harmony in the shape and functions of 
the organs of animal life, the most striking differences 
may take place between the organs of organic life, with- 
out much disturbance in the general result. For ex- 
ample, in disparities of the kidneys, of the lungs, of the 
salivary glands, &c, their functions are not, by any 
means, the less perfectly performed. The circulation 
remains the same in the midst of the frequent varieties 
of the vascular system on the two sides of the body, 
whether those varieties exist naturally, or whether they 
depend upon artificial obliterations of the large vessels, 
as in aneurism. 

Another very striking difference in the two lives may 
be observed in the duration of their action. All the ex- 
cretions proceed uninterruptedly, though not uniformly. 
Exhalation and absorption succeed each other incessant- 
ly; assimilation and dis-assimilation follow the same rule. 
On the other hand, every organ of animal life, in the ex- 
ercise of its functions, has alterations of activity and of 
complete repose. The senses, fatigued by long applica- 
tion, are for the time, disqualified from farther action. — The 
Ear is no longer sensible of sounds : — The Eye is closed 
to Light; — Sapid bodies no longer excite the Tongue; 
The Nose is insensible to odours ; — And the Touch be- 
comes obtuse. Fatigued by the continued exercise of 
perception, of imagination, and of memory, the brain has 
to recruit its strength, by a state of complete inactivity 
for some time. The muscles, relaxed by fatigue, are in- 



xliv 



VITAL FUNCTIONS. 



capable of farther contraction, till they have been permit- 
ted to rest; hence the necessary intermission, in every 
individual, of locomotion and of voice. 

This intermission of action is sometimes extended to all 
the organs of animal life at the same time ; on other occa- 
sions, only a part of them is affected by it. It is in this 
way that the brain frequently continues in the active ex- 
ercise of thought, while the senses, as well as the powers 
of locomotion and of voice are suspended. 

In addition to the foregoing views, it has also been sug- 
gested by Bichat, that another striking difference between 
organic and animal life, is found in the epoch and mode 
of their origin. Organic life exists from the first moments 
of conception; but animal life does not commence till 
after birth, when exterior objects are established in a cer- 
tain relation with the individual. It is more than pro- 
bable, that the functions of the Eye, the Ear, the Tongue, 
and the Nose, do not exist in such manner as to commu- 
nicate their several sensations in the foetus ; and that the 
enjoyment of a sort of indistinct sense of touch arising 
from its striking against the parietes of the womb, is the 
only circumstance which can give the latter any idea of 
its existence ; it is, however, doubtful whether it has even 
a consciousness on that point. The organic life, on the 
contrary, of a foetus, though not so complicated as after- 
wards is still remarkable for the promptitude and vigour 
of some of its functions, particularly of assimilation ; and 
in a very short time after birth, all the organs which it 
employs reach their highest degree of perfection, and 
thus present a very different case from the organs of 
animal life. 

The distinction of the two lives is farther kept up in 
their manner of ceasing in old age. Natural death, says 
Bichat, is remarkable, in terminating animal life almost 
entirely, a long time before it does organic life. The 



ANIMAL LIFE. xlv 

functions of the first cease successively. The Sight be- 
comes dim, confused, and is finally extinguished. The Ear 
receives the impression of sounds indistinctly, then faint- 
ly, and afterwards they are entirely lost upon it. The 
skin becomes shrivelled, hardened, loses many of its ves- 
sels, by their obliteration ; and is only the seat of an ob- 
scure and indistinct touch ; the hair and beard become 
white, and fall from it. The nose loses its sensibility to 
odours. Of all the senses, it has been often remarked, 
that the Taste remains the longest, and exhibits the last 
efforts of animal life. 

The powers of the mind disappear along with those of 
the senses. The imagination and the memory are extin- 
guished ; the latter, however, under striking circum- 
stances. The old man forgets, in an instant, w T hat was 
said to him, because, his external senses being weakened, 
do not confirm sufficiently the impression on his mind : 
he is, however, able to recollect the transactions of early 
life, and sometimes retains a vivid impression of them. 
He differs from the infant in this, that the latter forms 
his judgments from what is passing, whereas, the former 
forms his from what has already past. Both are, there- 
fore, liable to great errors; for, the accuracy of knowledge, 
in regard to things present, can only be obtained by com- 
paring them rigidly with other things. Locomotion and 
voice also participate in the decline of the other organs 
of animal life; their powers are intrinsically weakened ; 
besides which, a certain degree of inactivity is imposed 
on them, by the previous decline of the brain and senses. 

If we now consider, that sleep retrenches about one- 
third of the w ? hole duration of animal life ; that nine 
months of it are first lost in gestation; and that the ex- 
tinction of our senses is the inheritance of old age; it will 
be seen how great is the difference between the whole 
duration of animal, and of organic life. 

It has been remarked by Bichat, that the idea of death 



xlvi 



VITAL FUNCTIONS. 



is painful to us only because it terminates our animal 
life, or those functions which put us in relation with sur- 
rounding objects. This is the privation which plants 
terror and dismay on the borders of the tomb. It is not the 
pain of death that we fear, for many dying persons would 
willingly commute death for an uninterrupted series of 
bodily suffering. But if it were possible for a man to 
exist whose death would only affect the functions of or- 
ganic life, as the circulation, digestion, and secretions; 
allowing the exercise of the senses and the mind to con- 
tinue, this man would view with indifference the extinc- 
tion of organic life ; because he knows that the happiness 
of living is not attached to it, and that he would remain 
after this partial death, still in a condition to appreciate 
all the delightful ties of existence.* 

* For a detailed exposition of the phenomena of the Animal and of the Organic 
Functions, see Human Physiology, by Robley Dunglison, M. D., Professor, &c., 
Jefferson College. Philadelphia, 1846. Principles of Human Physiology, by W. B. 
Carpenter, M- D. London, 1842. — Elements of Physiology by ditto. Phila., edition, 
1846. — And elements of Physiology, by J. Muller, M. D. translated from the German 
by W. Baly, M. D. London, 1840, also the Philadelphia edition of the same, ar- 
ranged by John Bell, M. D., 1843. 



CHEMICAL COMPOSITION. 



CHAPTER II. 



Upon the death of the body, the liquids and tissues 
which compose it are, when submitted to decomposition 
by chemical process ; found to consist of a number of ele- 
mentary ingredients which are common to it and to inor- 
ganic bodies, and amount to about twenty. 

These Chemical Elements as ascertained up to the pre- 
sent day to exist in a state of health; are, oxygen, hydro- 
gen, nitrogen, carbon, phosphorus, chlorine, sulphur, 
fluorine, potassium, sodium, calcium, magnesium, sili- 
cium, aluminium, iron, mangenese, titanium, lead, and 
copper: also iodine and bromine, which are almost ex- 
clusively from marine plants and animals. The oxygen, 
hydrogen, nitrogen, carbon, and phosphorus of themselves 
make the principal mass of the solids and liquids. The 
calcium is found in great qnantities in the bones in com- 
bination with phosphoric and carbonic acids; the other 
elements exist in much smaller proportions, there being 
but little more than a trace of them found upon the de- 
composition of any part. The metals and the metalloids 
are not in their pure state, but united to chlorine or in 
that of oxyde combined with carbonic, phosphoric or sul- 
phuric acid. They may be detected in the ashes of most 



xlviii 



CHEMICAL COMPOSITION. 



animal substances. The iron is considered generally as 
an essential ingredient in hematosin or the colouring prin- 
ciple of the blood, and in the pigmentum nigrum; it 
has been found also in the lens and in the hairs. The ex- 
istence of arsenic was asserted by Raspail and Orfila, who 
considered it to be introduced in phosphoric aliments, 
which always contain a small quantity of it. This un- 
expected declaration which must of course have a most 
important legal bearing, in cases of imputed poisoning, 
has been contested by Flandin and Danger ; who declare 
that what Raspail and Orfila consider as arsenical stains 
in their experiments, are equally produced by sulphate 
and phosphate of ammonia united to an animal substance. 

The most diffused chemical elements are the oxygen, 
hydrogen, nitrogen, and carbon : they are the most essen- 
tial principles of organic matter, as two of them at least 
must be present in every such compound. The other 
inorganic substances are found in much smaller propor- 
tion, and seem to be merely incidental to animal organ- 
ism so as to make out some physical condition, probably 
not absolutely essential to life. Among these the phos- 
phate of lime holds a high rank from its making about fifty 
per cent, of the skeleton, and n^ext to it is the carbonate of 
lime from its making about eleven or twelve per cent. of the 
same. The other incidental articles are found in very 
small fractional quantities, and appear more as matters of 
curiosity, than as striking contributions. The existence 
of some is even contested. 

Between the above organized matters and the fully 
formed texture, there is an intermediate condition result- 
ing from their combination into a series of organic corn- 
pounds, called proximate principles or organizable sub- 
stances. These exist in the Embryo, and are also ob- 
tained in the first stages of chemical analysis. The most 
abundant of them are Protein, Albumen, Fibrin, Casein 
and Colla or Gelatine; but there are many others in com- 



CHEMICAL COMPOSITION. xllX 

paratively small quantities, the traits of which will be 
presented in place. 

The manner of combination of the simple chemical ele- 
ments to form the above organic compounds, is not yet 
settled by Chemists. Some consider them as equally 
united, and view the organic compounds as ternary or 
quaternary in degree ; others hold that two or three of the 
elements form a compound radical, to which is united 
another so as to form a binary compound. The idea may 
be illustrated from inorganic Chemistry. Ether is formed 
by four atoms of carbon, five of hydrogen, and one of oxy- 
gen, the first two make a hypothetical radical called 
Ethyl, to which is united the one atom of oxygen; ether 
is thus an oxyde of Ethyl, and the formula of its composi- 
tion is Carbon, 4; Hydrogen, 5; + Oxygen, 1. 

In organic substances it is to be remarked that an union 
limited to two simple chemical elements is very rare, the 
almost universal rule being a compound radical of two or 
more substances united to an additional one. These or- 
ganized unions of chemical elements are remarkable too 
for the facility of their dissolution, both during the living 
and the dead state. 

Such obscurity prevails, however, on the real nature 
or condition of these organic combinations of chemical 
elements, that their reproduction in the laboratory by 
means purely scientific, has scarcely advanced at all. 
The examples at present are limited to the formation by 
Wohler of urea, from the cyanite of ammonia, in depriving 
it of a little ammonia by the influence of heat; — to al- 
lantoin, which is analogous to urea; — and to formic acid, 
which has likewise been elaborated by chemistry alone. 

The organic compounds of animals are found to a 
large extent also in vegetables. The first elaboration 
from the inorganic state occurring in the latter, renders 
them, therefore, highly suitable as food for man, the 
transition or modification being an inconsiderable one 

Vol. I. — e 



1 CHEMICAL COMPOSITION. 

from the vegetable to the animal condition. The blood 
is the grand reservoir for the introduction and distribution 
of these organic compounds, each of which has its utility, 
insomuch so that neither albumen, gelatin, casein, or 
fibrin alone will sustain life. 

Of substances, the result of organization and of a cha- 
racter essential to it is Protein, which is the base of all 
albuminous bodies both in the animal and vegetable 
kingdom. It exists in fact in every tissue of the animal 
and of the vegetable fabric, being found dissolved in their 
fluids and condensed in their solids. It may be obtained 
by dissolving boiled albumen in a weak solution of caustic 
alkali and then precipitating by the addition of an acid. 
The protein thus treated falls under the form of grayish 
white flakes. When starch is washed from wheat flour, 
so as to leave merely the gluten, the latter treated by the 
above process yields also protein. The protein obtained 
in both cases appears to be identical in its sensible and in 
its chemical properties, it is also made soluble by an alkali 
and precipitated by an acid. It is hence seen that the 
transition from the vegetable to the animal form of matter, 
is one of comparative simplicity. Protein is found abun- 
dantly in albumen, fibrin, casein, &c , united to a small 
quantity of sulphur, of phosphorus, or of salts, from which 
it is easily freed by certain chemical processes, the for- 
mulae for which may be readily found.* In a humid state, 
this substance is gelatinous, insipid, inodorous. It is inso- 
luble in water, alcohol, or ether. When dried it is brown, 
hard, and fragile. When pulverized, it makes a yellow 
amber-coloured powder. It attracts moisture from the air, 
and when placed in water, swells up and resumes its first 
condition. On chemical analysis it is found to be com- 

* See Henle.— Encyclop. Anat., Vol. VI.— Simon's Animal Chemistry. Philad. 
Edition, 1816. 



ALBUMEN — FIBRIN. li 

posed in a hundred parts of 16.01 of nitrogen, 55.29 car- 
bon, 7 hydrogen, 21.70 oxygen. 

Albumen is the most universal of the modifications of 
protein. A striking example of it is the white of an egg, 
where it is collected into a large agglomerated mass, but 
it is also found in the serum of the chyle, of the lymph, 
and of the blood, in the serosity of serous cavities, in pus. 
in pathological secretions, and in the greater part of the 
liquids secreted from the blood. Whatever tissue one 
examines, a proportion of albumen is always found in it, 
and it is also one of the constituent principles of the brain 
and of the nerves. Its natural state is one of fluidity, but 
it is easily evaporated to dryness, and then forms a bril- 
liant transparent mass of a yellowish colour. It is ren- 
dered firm or coagulated by heat, most of the acids, and 
by many of the neutral salts. Its natural disposition 
is to remain fluid or semi-fluid, it is only when under 
chemical influences that it solidifies. It is so nearly 
allied to protein, that, according to Mulder, it differs from 
it only by a very small introduction of phosphorus and 
of sulphur into it, both together making but one part in 
a hundred. 

Fibrin, another of the modifications of protein is also 
found in the blood, the lymph, the chyle, the serosity of 
serous cavities, and is remarkable for the quantity which 
is thrown out upon inflamed surfaces and in inflamed 
tissues. It constitutes the base of the muscular system. 

It resembles exactly in appearance albumen, and the 
principal characteristic distinction from it, is that of coa- 
gulating spontaneously. The blood of asphyxied per- 
sons, of animals dead from fatigue, of certain poisoned 
individuals, and of such as die of hemorrhage from trivial 
wounds, does not coagulate. It is hence inferred that, 



Hi CHEMICAL COMPOSITION. 

in such cases, the fibrin does not exist, for by some vital 
process it has disappeared. 

Under chemical analysis it seems to be almost the same 
with albumen, in Mulder's experiments it contained a 
little more sulphur with a trifling variation in the quan- 
tity of the other ingredients. It contracts with acids, 
neutral salts, and different bases, the same combinations 
with albumen. The most remarkable chemical difference 
between the two is their habit in regard to oxygenated 
water. Chlorohydric acid makes a violet colour with al- 
bumen, — and an indigo blue with fibrin. 

Casein, another of the products of protein is found 
principally in milk, but is not confined to it, as it exists 
also in the blood, the saliva, the bile, the pancreatic juice, 
in pus, in tuberculous matter, and elsewhere, also in ve- 
getables. 

There are several processes known to Chemistry for 
obtaining casein. One of the most simple is that of Mul- 
der, who adds acetic acid to milk, whereby the casein is 
precipitated, washes the precipitate in pure water repeat- 
edly, squeezes the water out on each occasion, and after- 
wards removes the grease with boiling alcohol. 

Dissolved in water casein is of a pale yellow and of a 
consistence somewhat mucilaginous. On being evapo- 
rated, it exhales the odour of milk, and covers itself with 
a white pellicle which upon being removed is renewed. 
On being perfectly dried it forms a mass of a yellow am- 
ber colour, easily reduced to powder, and which attracts 
the moisture of the atmosphere. In the humid or dis- 
solved state, the addition of alcohol makes it opaque, and 
to resemble coagulated albumen, this is produced by the 
abstraction of its water. It is soluble to a small extent 
in boiling alcohol, and from that state of solution it may 
be extracted without any change of its properties. 



casein. liii 

The analogy of casein with albumen and fibrin is very 
close in many respects, and especially in regard to its 
power of coagulation, or capacity to change its state, so 
that it is no longer soluble in water. 

Casein is coagulated by heat, by alcohol, by acids, and 
by rennet or the stomach of young animals. In boiled 
milk the skin or pellicle which forms upon its surface, is 
coagulated cheese. Alcohol precipitates it by abstracting 
the water which held it in solution. Many of the acids 
coagulate it freely, and notably the lactic acid which is 
produced from the sugar of milk, when the milk sours. 
Sugar of lead is a powerful coa^ulator of the same. The 
modus agendi of rennet or the dried stomach of young 
animals, in coagulating casein or milk is as yet inexpli- 
cable. Its influence, however, in this respect is truly 
remarkable. Berzelius coagulated 1800 parts of milk 
with only one of rennet, and found that the latter had 
lost only six per cent, of its weight. It is ascertained by 
experiment that pure casein dissolved in water is not co- 
agulated by rennet, but as the latter has that power 
upon casein dissolved in milk, it is hence suggested 
by Henle* as possible, that the rennet only acts indi- 
rectly by the conversion of the sugar of milk into lactic 
acid. 

Cheese which is prepared by rennet alone is called 
sweet cheese, and when prepared by lactic acid it is called 
acid cheese. It is supposed that it exists to a limited ex- 
tent already coagulated in fresh milk, inasmuch as the 
envelopes of the globules of milk appear under the mi- 
croscope to be insoluble casein. 

Common cheese is a composition of dried casein and 
of butter. Pure casein, according to Mulder, contains 
in one hundred grains 15.95 of nitrogen ; 55. 10 of carbon ; 
6.97 of hydrogen; 21.62 of oxygen, and 0.36 of sulphur. 

* Henlc, loc. cit. p. 46. 
E* 



liv CHEMICAL COMPOSITION. 

Casein contains a quantity of phosphate of lime amount- 
ing indeed to 6-^- per cent., the presence of which is of 
the greatest importance for the nutrition ot miants ana 
Tor the formation of bone. 

Pepsin. Is another combination of protein, and was 
discovered by Schwann in 1836. It is formed and found 
in the cells of the follicles and of the solid glands of the 
stomach, and may be obtained by macerating the mu- 
cous membrane of the stomach of an animal in water dis- 
tilled. A solution thus made may be precipitated by 
basic acetate of lead, and afterwards separated from trie 
lead by a particular process. This pepsin when largely 
diluted with water and mixed with a small quantity of 
acid constitutes an artificial gastric juice which dissolves 
albumen in six or eight hours; it has the same effect 
upon cartilage and upon cellular substance. It resem- 
bles very much albumen, but unlike it, cannot be pre- 
cipitated from its combinations with acids by the ferro- 
cyanite of potash. 

There are some substances in the composition of the 
body, which according to Professor Henle, ought not to 
be considered as belonging to its immediate materials. 
They are Globulin; Spermatin; Mucus; Dacryolin or 
the matter of the Tears; and the Horn-like produc- 
tions. 

Globulin. This material exists in the blood, and is 
the name given by Berzelius to a residuum of itobtained 
in a particular way. By diluting with water the red 
globules of the blood, they become transparent, swell up, 
and at last disappear, seeming to have been dissolved ; 
but they may in fact be brought into view again by 
Iodine, which renders them opaque, thereby showing 
that the colouring matter may be extracted by water, and 
still leave the globules behind. By evaporating to dry- 



GLOBULIN — SPERMATIN. lv 

ness blood diluted with water, if alcohol be added, the 
colouring matter will be taken up by the alcohol, and the 
globules will be left; this residuum then is the globulin 
of Berzelius, and the colouring matter dissolved by the 
alcohol is the hcematosin. 

Globulin upon trial by chemical analysis is almost 
identical with albumen and seems to be such in reality, 
it is, therefore, upon good grounds placed by Mulder 
among the combinations of protein. It is formed by the 
capsule of the blood discs, with perhaps the nuclei. 
When extracted according to the process of Lecanu with 
sulphuric acid, its analysis furnishes the following parts : 
nitrogen 15.70; carbon 54.11; hydrogen 7.17; oxygen 
20.52 ; sulphuric acid, 2.50, which corresponds nearly 
with four atoms of protein to one of anhydrous acid. 

Spermatin is a fluid derived from the semen of ani- 
mals. At the moment of obtaining the semen in a fresh 
state, it is placed in alcohol, upon which it contracts in a 
few minutes an opaline colour and forms a clot, like a 
pack thread, collected into a small bundle or hank. It 
may be dried in this state, when it forms a bunch of fila- 
ments of the colour of snow. The article thus coagulated 
constitutes the spermatin of Berzelius, of Vauquelin, and 
of John, by the last two of whom it was discovered. It 
mav be identified by certain characters or habitudes in 
regard to water, mentioned by Berzelius. 

This fluid shows under the influence of chemical agents 
a close analogy with albumen. An analysis of it, how- 
ever, must, to a large degree, be inconclusive, as the 
seminal fluid from which it is obtained is a mixture of 
the secretion of the testicles — of the vesiculse seminales — 
of the prostate — of the glands of Cowper and of the ure- 
thra — besides containing scales of epithelium — corpuscles 
of mucus and spermatic animalcules. 



Ivi 



CHEMICAL COMPOSITION. 



Mucus. Heretofore every thing has been considered 
mucus which came from the surface of a mucous mem- 
brane, excepting certain secretions of a decidedly specific 
character, as the saliva, the bile, the urine, and a few 
more. It is now, however, ascertained that in the fluid, 
commonly called mucus, there are at least three dissimi- 
lar constituents, to wit: — the waste of the epidermic mu- 
cous membrane, pus, and the mucous secretion itself. 

The epidermic waste or molt, resembles the scaly ex- 
foliation which is incessantly in progress from the cuti- 
cle; and is formed by the desquamation of the superior 
layers, which, as they fall off, are succeeded by others. 
These scales are washed off by the fluid secretions of the 
part, and make to the mucous membrane a glairy coat- 
ing, which is easily removed by scraping and by a stream 
of water. The pus is found in catarrh, coryza, blennor- 
rhagia, fluor albus, and diarrhoea; and is formed from a 
liquid mixed with granules of a certain kind, coming 
from beneath the Epidermis of the mucous membranes. 
The mucous secretion is the product of the muciparous 
glands, and is for the mucous membranes what the per- 
spiration is for the skin. It also is considered to be ela- 
borated by the epithelial cells of mucous membranes, 
which in this process are constantly liquefying or bursting 
open. 

Mucus from the nose, according to the analysis 

of Berzelius, consists in Mucin essentially - 5.33 
An extract soluble in alcohol and an alkaline 

lactate - 0.30 
Chloride of Soda and of Potash - 0.56 
An extract soluble in water, with traces of albu- 
men and of a phosphate - - - 35 
Soda -----. o.09 
Water - - - - . - 93.37 

100.00 



EXTRACTIFORM SUBSTANCES. lvii 

Lachrymal Matter or Dacryolin. This is found as 
a residuum upon the evaporation of the tears in the open 
air. In this condition it forms a yellow and insoluble 
mucus, which neither heat nor acids coagulate. Four- 
croy and Vauquelin find in it one per cent, of a solid sub- 
stance seeming to be chloride of soda principally ; and the 
remainder of this one per cent, is probably mucus and 
the scaly molt of the epithelium. 

The Horn-like tissues, are represented by the nails, the 
hair, and the epidermis. It was once supposed that they 
were formed from a fluid which dried up, but it is now 
known that in the case of each one, the primordial state 
is that of a cell, with a contained substance and a nu- 
cleus: and that it is an aggregation of such cells in a col- 
lapsed state, but adhering to one another which consti- 
tutes the substances above alluded to. 

The cells or scales of the epidermis are held together 
by an intermediate substance which dissolves in weak 
acids, and allows the scales to separate and float about, 
giving to them the fallacious appearance of being dis- 
solved also. 



Extractiform Substances. 

After removal of the combinations of protein from ani- 
mal matter, a nitrogenous organic residuum still remains 
mixed up with certain saltsaslactates> chlorides,phosphates 
and sulphates. What remains upon the separation of the 
salts by their appropriate solvents constitutes the Extrac- 
tive Matter. Animal extractive is very generally diffused 
in the tissues and humours of the body, but is found in 
greater abundance than elsewhere in the muscular flesh. 
This matter is readily obtained by steeping a part in aque- 
ous alcohol, and then evaporating the latter entirely. If 



lvili CHEMICAL COMPOSITION. 

pure alcohol be poured upon this dry residuum, it removes 
from it a substance called the alcoholic extract, and what 
is left constitutes the aqueous extract being soluble alone 
in water, and constituting what Thenard has called 
Osmazorne (from «o>uj and £*,««, smell and soup) it is found 
abundantly in soups or bouillons, and in them is mixed 
with gelatine in the proportion of one part to seven of 
gelatine. It is the osmazorne which gives flavour spe- 
cifically to soups and meats. The extractive matter pre- 
sents itself in several soluble forms — one the water extract 
is soluble in water but not in dilute alcohol — another is 
soluble in dilute but not in anhydrous alcohol, it is the 
spirit extract — a third the alcoholic extract is soluble in 
water, in dilute alcohol and in anhydrous alcohol. 

The extractiform substances show themselves under 
several modifications when tried by chemical tests, the 
process whereby they may be detected are set forth in 
the works on organic chemistry.* One is called Ptya- 
lin, from its being found in the salivary secretion, ano- 
ther Kreatin, from its being found in the liquids of meat. 
There are also several others which may be distinguished 
by different chemical agents. 

Glue, or Colla. 

Glue may be obtained from many animal tissues, but 
never exists in them in that state, and is produced by 
boiling them in water. The substances most productive 
of it, are bones, cartilages, tendons, cellular tissue, and 
ligamentous matter. The tendons and true ligaments 
are so prone to this transformation, that they yield a 
weight of glue equal to their own weight, both beino- 
dry. 

In the process of producing glue by the action of boil- 

* See Henle. Also Simon, on Animal Chemistry. 



CHONDRIN — PYIN. lix 

ing water, there is neither a disengagement of gas, nor an 
absorption of any of the constituents of the atmosphere. 
Acids, much diluted favour the process. The substances 
which yield glue in the fully organized body, if treated 
m the sme way during the earlier periods of development, 
produce what is called Pyin, a matter differing from 
glue. The common characters of glue are so well known 
as not to require a description on the present occasion : 
its chemical analysis, according to Mulder, yields in one 
hundred parts, 18.350 nitrogen, — 50.048 of carbon, — 
6.477 of hydrogen, — and 25.125 of oxygen. It has also 
a very small quantity of phosphate of lime in it. 

Chondrin. 

Chondrin, resembles in many respects glue, and was 
first discovered and designated by J. Muller.* It is ob- 
tained by boiling in water the cartilaginous rudiments of 
bones, the articular cartilages, the fibro cartilages of the 
nose, ear, larynx, trachea and some other parts, as the 
cartilages of the ribs. It requires a more protracted boil- 
ing than common glue to produce it, and is the base of 
the permanent cartilages. It is precipitated from solution 
by alum, sulphate of alumina, acetic acid, and acetate 
of lead. Mulder's analysis showed in its composition 14. 
44 of nitrogen, — 49.56 of carbon, — 6.63 of hydrogen, — 
28.59 of oxygen, — 0.38 of sulphur. Like glue, it con- 
tains about 6 per cent, of inorganic matter, chiefly phos- 
phate of lime. 

Pyin. 

Pyin discovered by Gueterbock, in pus, whence its 
name, is found also elsewhere; as in mucus, in tuber- 

* Elem. Physiol, vol. i., p. 390. 



lx CHEMICAL COMPOSITION. 

culous matter, in granulations, in false membranes of a 
recent date, in the skin of a foetus, in condylomatous pro- 
ductions, and in fine, wherever there is a cellular sub- 
stance imperfectly developed. . It is obtained by adding 
alcohol to pus, which precipitates thepyin with albumen, 
it may then be separated from the latter by water. The 
principal test for it, is alum, which precipitates it in floc- 
culi from a state of solution. 



Hcematin, or Hcematosin. 

Heematin is the colouring matter of the blood, and is 
found in the blood discs or globules, though under cer- 
tain circumstances, it is free in the liquor sanguinis or 
the fluid part. It is thought that in some certain states 
of the blood, the blood discs being formed as they are, of 
a vesicular envelope and a contained fluid, when the 
liquor sanguinis is too much inspissated some of the fluid 
of the blood discs leaves them by exosmosis and joins 
the liquor sanguinis, the vesicle becoming somewhat col- 
lapsed ; and on the contrary, if the liquor sanguinis be too 
fluid, the vesicles absorb some of this fluid and become 
turgescent. While in the former process, the solid con- 
stituent of the blood discs, as the hcematin, passes out- 
wardly and may become mixed with the liquor sanguinis. 

Pure hsematinmay be obtained by several proceedings 
known to the operative. chemist, as through the reaction 
of alcohol, of ether, and of sulphuric acid. According 
to Muller, its chemical composition in 100 parts is, Nitro- 
gen 10.54, — Carbon 66.9, — Hydrogen 5.30, — Oxygen 
11.01, — Iron 6.66. In a dried state it has a dark-brown 
colour, with a few brilliant points, and it is insipid and 
inodorous. 



UREA AND URIC ACID. lxi 



Bile. 

This secretion is formed by a resin, according to The- 
nard of a green colour, not very soluble in water and 
completely soluble in alcohol. It also contains Picromel,* 
or a biliary sugar. This is colourless and inodorous, 
has a sweet taste which endures for some time in the 
mouth, and is also in a slight degree bitter. In addition 
to the preceding constituents of bile, there is Taurin — 
Cholic acid — and a colouring matter. In a recent ana- 
lysis of the bile, by Berzelius, he has been induced to 
believe, that the principal element of bile is a substance 
which he calls Bilin, easy to decompose, and by the aid 
of acids convertible into several other bodies. 



Urea and the Uric Acid. 

Urea is found principally in the urine. It is also in 
the blood and in the secretions from it, when the function 
of the kidneys has been invaded either by disease or by 
the ablation of these organs. 

It is readily obtained by evaporating the urine to a 
syrup, then adding nitric acid to it, so as to make a nitrate 
of urea. The nitric acid may afterwards be detached 
by carbonate of barytes, and the urea being then dis- 
solved in alcohol, the latter is driven off by evapora- 
tion. 

Uric acid is found in the urine of carnivorous animals, 
and also in urinary and in arthritic calculi. The urine 
of serpents and of birds is formed almost wholly from the 
urate of ammonia. This acid is precipitated in a state, 
almost perfectly pure, from the human urine by the in- 

* Called from its bitter sweet taste. 

Vol. I.— f 



lxii CHEMICAL COMPOSITION. 

fluence of a low temperature. The precipitate is at first 
powdery and gray, the colour afterwards changes to a 
pale rose hue— and by drying, it assumes the form of 
scales, which are the smaller as the acid approaches a 
pure state. 

The preceding substances enumerated and described 
as Protein and its products— also the Extractiform Sub- 
stances—the Collin, or Gluey ones— Ha3matin— the con- 
stituents of Bile— Urea and Uric acid are all distinguished 
by a large proportion of nitrogen in their chemical com- 
position. 

We have next to take into consideration certain animal 
matters, which are destitute naturally of Nitrogen — these 
are Sugar of Milk — Lactic acid— Saponifiable Fats— 
the Non-Saponifiable Fats — Fatty Bases — and Fatty 
Acids. 



Sugar of Milk. 

Sugar of Milk is found in the milk of woman and in 
that of the females of all mammiferous animals. In some 
cases where the secretion of the mamma has been sup- 
pressed, it has been found, or, at least, supposed to be in 
the fluids, secreted from the intestines or deposited in the 
peritoneal cavity. A case of the latter kind occurred to 
Schreger in the year 1800.* 

It makes about two-fifths of the solid residuum of milk 
when this fluid has been evaporated to dryness, and may 
be obtained, by depriving the milk of its butter and cheesy 
matter, and then evaporating it to the consistence of a 
syrup. When it gets cool the saccharine matter is depo- 

* Encyclop. Anat., p. ] 00, vol. vi. 



LACTIC ACID. lxiii 

sited in crystals, and it may then be purified by successive 
solutions followed by crystallizations. 

The specific gravity of sugar of milk is 1.543. Its 
crystals are four-sided prisms, having a lamellar arrange- 
ment and ending in pyramids with four faces. It is much 
harder than sugar candy, has a moderately sweet taste, 
and one which is somewhat gravelly. It is soluble in 
about six parts of cold water, but does not dissolve in 
pure alcohol or in ether. The properties of it are some- 
what different when taken from the human female and 
from the cow. Its concentrated aqueous solution turns 
spontaneously into lactic acid. Its elements, according 
to Liebig, are 12 atoms of Carbon, 24 of Hydrogen, and 2 
of Oxygen. Various compounds are formed by treating 
it with chlorine, sulphuric acid, nitric acid, and other 
articles. 

Lactic Acid. 

Lactic Acid exists either free or in combination with 
different bases, in all the liquids and secretions of the 
body. In the free state, it is found in meat, in perspira- 
tion, in urine, and in milk. The bases with which 
it is in combination, are soda, potash, lime, magnesia, 
ammonia, and urea. It is not only obtained from animal 
matter, but is produced in the fermentation of certain 
vegetables which produce starch and sugar. 

The process for getting it from milk is as follows. A 
quantity of sour whey is to be evaporated to one-sixth of 
its weight, and then filtered. The phosphoric acid in it 
is then precipitated by chalk, and afterwards the excess 
of the chalk is to be corrected by oxalic acid. The liquor 
is then filtered again, the fluid part of it is evaporated, the 
lactic acid is then taken up by alcohol which leaves the 
sugar of milk. The alcohol is then to be evaporated, and 



lxiv CHEMICAL COMPOSITION. 

the residuum is Lactic Acid, to purify it, however, 
perfectly, requires some other steps well known to che- 
mists. 

The lactic acid does not continue in the dry or anhy- 
drous state, unless in combination with some base. When 
in the pure hydrated condition, it forms a colourless 
syrup, extremely acid, without smell, and having a spe- 
cific gravity of 1.215. It is only dissolved to a very 
small extent in ether, but has no limits as regards water 
and alcohol. It coagulates albumen and casein, and its 
action is much accelerated on them by the assistance of 
heat. It was formerly confounded with acetic acid, but 
the difference is now well established in its want of vola- 
tility and of odour. 

Lactic acid dissolves phosphate of lime very rapidly, 
by which quality is explained the quantity of this salt 
held in solution by milk, urine, and other secretions. 
It has also been suggested by Marchand, that the 
presence of an excessive quantity of this acid in the 
system, causes a softening of the skeleton by preven- 
ting the deposite of phosphate of lime into the bones, 
and also dissolving that which already exists in them. 
Its atomic proportions are, Carbon 6, Hydrogen 10, 
Oxygen 5. 

It is kept very conveniently in the form of lactate of 
barytes, or of lead, and forms with these bases a mass, 
which resembles gum. Being superior in strength to 
acetic acid, it drives it from its combinations. Boiled in 
strong nitric acid, the latter acid seizes to some extent 
upon its oxygen, and produces oxalic acid. 

Fatty Substances. 

These productions of the animal body, are destitute 
of nitrogen, and, as a common character, are insoluble 
in water, but soluble in hot alcohol and in ether. Some 



FATTY SUBSTANCES. lxV 

of them are saponifiable or capable of being converted 
into soap by union with an alkali ; the same also unite 
readily with oxides of lead, so as to form plasters. 
This habit is in virtue of an acid existing in them, 
and which, being naturally united to a base, leaves 
that base and attaches itself to another, as the alkali 
or the lead. The acids and the bases themselves are 
oxyds of compound radicles, supposed to be carburets of 
hydrogen. 

Another series of fatty bodies cannot be converted 
into soap, and there is a doubt among chemists how they 
ought to be classed, whether among the fats which have 
a base, or as neuter organic matters. Among these pecu- 
liar organisms, are Cholesterin and Serolin. 

Cholesterin is found in bile, hence its name, also in 
the blood, and in the medullary nervous matter ; it is also 
observed in the secretions, in morbid tissues, in cj^sts, 
in hydatids, in the water of dropsy, in medullary fungi 
and in other tumours. 

Cholesterin, in its pure state, crystallizes in lamina?, of 
a brilliant mother of pearl colour, soft to the touch and 
sometimes very large. It is inodorous and insipid, dis- 
solves readily in hot alcohol or ether, but not in water. 
It may be obtained from biliary calculi by boiling them 
in water, and afterwards in alcohol ; when the latter cools, 
the cholesterin is separated by crystallization. Its che- 
mical components are carbon 85.095, Hydrogen 11.880, 
Oxygen 3.025. Treated with nitric acid, it forms cho- 
lesteric acid. 

Serolin, is called from its being obtained from the 
blood, an original observation of Boudet. It may be 
procured by boiling dried blood in alcohol ; it separates 
from the latter on its cooling, and floats about in flocculi 
of a pearl colour, of a fatty feel, and acting neither after 

Vol. I.— g 



1XV1 CHEMICAL COMPOSITION. 

the manner of acids nor of alkalis. When examined 
by the microscope, it is seen to consist in filaments, which 
are swollen out in a globular form from place to place. 
It is susceptible of sublimation almost without any al- 
teration. 

Of the Saponiftable Fats. 

There are three substances which perform the part 
of base to animal fat: glycerin, the oxyd of cetyle, and 
cerain. The first forms the base of human fat, and is 
more universally diffused in the animal kingdom ; the 
second exists in spermaceti ; and the third in wax. 

Glycerin is separated from fat in the act of the latter 
forming soap with an alkali, but it may be obtained in 
the highest purity by boiling an oxyd of lead in fat, the 
acid of the latter attaches itself to the lead, and the gly- 
cerin is left free, being dissolved in the water from 
which it may be disengaged and purified by a particular 
process. 

Glycerin is a clear liquor, somewhat yellow, without 
odour and somewhat sweet : it is very soluble in water or 
alcohol ; not soluble in ether. It dissolves readily iodine, 
the vegetable acids, the deliquescent salts, the sulphate of 
soda, of potash, of copper, nitrate of silver, and many 
other articles. 

Glycerin being the base of human fat, the acids which 
are found in combination with it, are the stearic, mar- 
garic, and oleic; and the result of such combinations 
forms the fatty textures, called stearin, margarin, and 
olein. Butter has also its own peculiarities in being 
formed of glycerin, in union with butyric, capric, and 
caproic acids, and even the cerebral matter presents a 
peculiar acid united to glycerin, and called by Fremv, 
the cerebric acid ; and an oleo-phosphoric acid. 






SAPONIFTABLE FATS. lxvii 

The Stearic and Margaric acids are obtained pure by 
a process which is complicated and prolonged ; they are 
very feeble, but at an elevated temperature drive carbonic 
acid from its combinations. Their union with glycerin 
makes the principal part of the fat of the human bodj^. 
The Oleic acid is an oleaginous liquor, of a clear yellow : 
it is very acid, and has a rancid smell and taste. It is 
insoluble in water, but very soluble in alcohol. The 
olein which it forms by union with glycerin is in a fluid 
State naturally, but is kept so at degrees of temperature 
varying in the different animals. 

The above acid and basic constituents of animal fats 
are seldom found insulated, being almost always under 
the combinations alluded to above; a departure from this 
rule exists occasionally with the acids, but never with 
the base or glycerin. The fats under the form of stearin, 
margarin and olein are blended in the adipose tissue of 
the cellular substance, and in the fat of the bones or mar- 
row as it is called. The consistence of the fat depends 
upon their relative quantity in it. Thus Olein predomi- 
nates in oil or the fluid part of fat, it commonly not being 
in great quantity in the human subject ; but there are in- 
dividuals of enormous obesity, in whom its proportion is 
excessive, so that in making a necropsy of such in warm 
weather, the oil runs all about. Margarin is next in con- 
sistence, and forms lard, such as is found in the hog and 
in the bear. Stearin forms suet, and is found to a remar- 
kable degree in the fat of the sheep, and of the bullock. 

Fat, besides being in the cellular substance and in 
bones, prevails to a great extent elsewhere in the human 
body, as in the composition of the brain. It is found in 
chyle, blood, pus, bile, milk, and sometimes in urine. In 
milk and chyle its globules are in little vesicles. Its dif- 
ferent modifications exist in the vegetable kingdom ; as 
stearin in the cocoa-nut butter; margarin in palm oil ; 
and olein in flax-seed oil, and many others. 



HISTOGENY* 



ORIGIN OF THE ELEMENTARY TISSUES. 



CHAPTER III. 



In animals we find at an early period of their evolu- 
tion, and during their whole life, corpuscles so exceed- 
ingly fine as to require a microscope to see them dis- 
tinctly. They have a certain characteristic shape and 
are called elementary cells, primitive cells, and also nu- 
cleated cells, from the existence of a small point or nu- 
cleus within them. They are, in fact, vesicles with pa- 
rietes extremely attenuated, contain a fluid of some kind, 
occasionally granular; and have attached to their walls or 
lying loosely a smaller body, which is called the ker- 
nel or nucleus, and also Cytoblast in the language of 
Schwann. The nucleus presents, on most occasions, one 
or two spots or points, of a regularly rounded shape, and 
which go under the name of nucleoli. The nucleus 
itself is of a rounded or ovoidal shape, somewhat flat- 
tened, is colourless or of a reddish yellow, smooth, or 
granular like a raspberry, in which case its nucleoli 
are imperceptible. Its diameter is from the two to the 
four thousandth part of a line, or from the ~ — to the 
-g-^- of an inch. This nucleus appears sometimes itself 

* From Ie-TOf texture, and ymo-is generation. 



ELEMENTARY CELLS. liix 

to be made out of a membranous envelope with a con- 
tained fluid. 

The above elementary cells, at an early period of their 
existence are soluble in acetic acid, the nuclei being left 
behind, the nucleoli are to the same degree indestructible 
by this agency. The nucleoli are of a doubtful charac- 
ter, it being unsettled whether they are stains, globules, 
lacunse, or vesicles in the nuclei. Schwann says, that 
they are upon the outside of the nuclei in the round cells, 
and on the inside of the nuclei of the concave cells. 

The walls of primary cells are homogeneous or amor- 
phous, i. e. they appear to have extension with the least 
conceivable thickness, are perfectly smooth under the 
highest magnifying powers, and have neither filaments 
nor granulations, or any thing else indicative of an inter- 
rupted surface. The best idea of them would, perhaps, 
be derived from the inspection of a very small soap 
bubble. 

The elementary cells are situated in a substance also 
amorphous, and called by Schwann* Cytoblastema, and 
which executes the office of an intercellular substance. 
When this intercellular substance is liquid, the primary 
cells float freely about in it, as in the case of the blood ; 
but when the cytoblastema has more consistence, the 
cells are fixed to their places, and even glued together 
with some tenacity; with a force, in fact, requiring a spe- 
cial solvent to free them. 

The progress of these primary cells may be studied in 
the incubated egg, in the tissues of the body which are 
in a constant state of reproduction, as the nails and hairs, 
and also in the exudations of fibrin which occur on in- 
flamed surfaces. The vegetable kingdom, also, accord- 
ing to Schwann, presents analogies or repetitions of the 
process, precisely identical with what occurs in the ani- 
mal kingdom. 

* From jii/toc cell, fihmroc, germ. 
G* 



lxx 



HISTOGENY. 



The phenomena are as follow. An amorphous fluid 
by some internal change becomes granular. This amor- 
phous fluid is gum in a plant, but albumen in an animal. 
The first perceptible change from this condition of uni- 
form and unclouded transparency, is the appearance of 
numerous extremely minute granules, which make the 
fluid turbid. This state having remained for a short time, 
certain granules larger and more defined than the others 
are seen, and appear to augment by collecting the finer 
ones around them. This is the first state of nucleus, or 
cytoblast, or cell-germ, as it is also called.* From the 
surface of each cytoblast a delicate membrane rises up in 
an attitude resembling that of a watch glass to the dial; 
this membrane increases in extent and magnitude, until 
it envelops the cytoblast so completely that the latter is 
seen merely as a nucleus on its wall. The consistence 
of the cell is for some time very soft, and occasionally it 
disappears from trifling disturbances, as a slight agitation 
in the surrounding fluid. 

According to Schleiden, the function of the nucleus 
ends with the evolution of the cell, but others hold that 
the granules of which it is composed become the germinal 
points of other cells, to be developed within the original 
one. 

The elementary granules being the first indications of 
a rule of form, or distinctly defined shape, the opinion 
is entertained, from the present state of our knowledge, 
that they are vesicles consisting in a small sphere or par- 
ticle of fat, enveloped by a membrane. The existence of 
a membrane, though then invisible, would seem to be 

* The discovery of this germinal coagulation as the first formative act has been 
attributed to Schleiden, see Mailer's Archives, 1838, and to Schwann, sec Mikrosko- 
pische, &c, 1839. A much more ancient author may, however be quoted with greater 
propriety in the following words, Nonne sicut lac mulsisti me, sicut caseum me 
coagulasti, Job, x. 10. Hast thou not poured me out as milk and curdled me like 
cheese?" 



ELEMENTARY CELLS. lxxi 

proved by the circumstance, that the spherules are kept 
apart in this miniature state, but when they have aug- 
mented, then the exterior envelope is absolutely seen. 
The envelope itself is considered as a modification of 
protein, and is soluble in acetic acid, upon which act 
the granulations readily coalesce, and are easily dissolved 
in boiling ether or alcohol, which they had previously 
resisted. 

The above modification of protein is, probably, albu- 
men ; and an observation bearing on this point was origi- 
nally made by Ascherson. — To wit: that albumen never 
fails to coagulate in a membranous form when it comes 
in contact with fat. Under this law a particle of grease 
cannot for a moment be in contact with albumen, without 
the latter being drawn over it in a membranous form. 
A drop of each of these substances in a fluid state put in 
contact on a plane surface, exhibits instantaneously this 
phenomenon, in the formation of a delicate and elas- 
tic membrane around the fat, and which covers itself 
with numerous elegant folds. Oil and albumen shaken 
in mass together, exhibit the same upon a larger scale. 
A decisive proof of the existence of the capsule of albu- 
men thus formed, is that a process of exosmosis and of 
endosmosis occurs in its parietes, so that a fluid having 
an affinity for the oil makes the capsule expand or con- 
tract into wrinkles, according to circumstances* upon its 
being brought into contact with the capsule. 

This striking experiment has been seized upon by 
Henle to elucidate what occurs in the formation of living 
elementary granules. Fat and the combinations of pro- 
tein are incessantly introduced into the system by the 
action of the animal organism on aliments, so that they 
are found in the chyle, in the blood, and in all the fluids 

* Encycl. Anat., vol. vi., p. 164- 



lxxii HISTOGENY. 

of the body. The fat on its formation becomes quickly 
surrounded by a film of albumen, so as to prevent its 
particles from collecting into masses of large size, and the 
particles thus situated may become elementary granules 
in being deposited in the texture of organs. 

It is not, however, pretended that a process so purely 
physical as the formation of a film around a drop of fat 
gives all the explanations requisite for the understanding 
of a vital process; for an organic cell and an artificial one 
are as different from each other, as a dead body is from a 
living one. Chance alone produces the resemblance so 
far as it exists in form; the vital force of one makes after- 
wards an incomprehensible and unlimited difference. 

It may here be remarked that the globules of fat com- 
mon to the fluids of the body are kept when in a healthy 
state within certain limits of magnitude; and that in the 
case of pus, it is of a bad nature when the fat globules 
collect into large drops, hence the latter are seldom or 
never seen in pus of a good quality. 

In the estimate of the sources of elementary cells, it 
may also be remarked, that there is another act of the 
animal body exhibiting some analogy. It is known, for 
instance, that fibrin in coagulating, forms naturally a 
reticulated or cellular arrangement containing serum; in 
some cases even vesicles are thus produced, when a clot 
remains for some time in a living vessel or canal ; and 
sometimes such vesicles are seen erecting themselves so 
as to be appended only by a pedicle. Henle has seen 
this assumed cellular arrangement containing serum, in 
polypi of the heart; in the membrane of croup; and in the 
plastic exudations of the womb, and of the intestinal 
canal. He concludes, therefore, that many hydatids 
come from such cells taking on a spontaneous growth. 
Dujarden has observed a similar process to the above in 
an exudation, which he calls Sarcode, coming from the 



ELEMENTARY CELLS. lxxiii 

bodies of dying infusory animalcules, and from the frag- 
ments of the higher animals. In this matrix is generated 
small insulated globules, that finally acquire a larger 
size at the expense of the matrix, which ultimately col- 
lapses, and is reduced to a very small residuary matter.* 

Another hypothesis in histogeny is that of Raspail and 
of Schwann, who see in the elementary cells phenomena 
analogous to the formation of crystals in inorganic matter ; 
the difference being that these organic crystals execute 
an imbibition of new molecules for their growth, while 
inorganic crystals grow merely by super-position. The 
points in detail of this theory are so much in the line of 
gratuitous assumption, that much remains yet to render 
it acceptable. 

Upon the multiplication of cells depends the reproduc- 
tion and growth of the body. In some cases these cells 
are secreted in succession from a matrix; which in the 
case of the epidermis, the nails, and the hairs, is the cutis 
vera. Each cell in them is developed in an insulated 
manner, and reaches its perfect state by its formative 
force alone. This occurs in tissues having but an infe- 
rior degree of vitality as the above. But in the majority 
of instances, the formation of one cell depends upon the 
action of pre-existing cells. It becomes an act of gene- 
ration, wherein, the new cell forms .at first an appen- 
dage of an older one; the older cells finally disappear and 
are succeeded in full by the new cells; and this act of 
succession in generations is constantly going on during 
the life of the individual. This process reduces animal 
life to an evolution of cotemporaneous and intercurrent 
generations of monades: each generation parting with its 
vitality in behalf of proximate succeeding generations, 
but in such a way that the life of the whole system is 
continually kept up. In general death, the act of rege- 
neration, is of course universally arrested. 

* Henle, Encycl. Anat., vol. vi., p. 168. 



lxxiv 



HISTOGENY. 



The generation of cells as above is produced in two 
ways, one called exogenous from its occurring in the form 
of an excrescence or sprout on the exterior of preceding 
cells. Henle considers this act to be confined to the 
lower conditions of vegetable life.* On the contrary, 
Muller asserts it as of common occurrence in many ani- 
mal tissues. In this case the cytoblastema or matrix, of 
the new cell is on the exterior of the older one. The 
other mode is called endogenous, because it occurs within 
the circle of the old cell from the cytoblastema which it 
contains. The most conclusive proof of the latter is pre- 
sented in the development of the Embryo, at the expense 
of the granular contents of the yolk of an egg. From the 
observations of the German physiologists it appears, that 
in certain molluscous animals the first act of evolution of 
a germ is the appearance of three or four globules, these 
contain others, which grow in their turn, and distend the 
preceding; then a third generation occurs within the 
walls of the second, and so on successively until a homo- 
geneous mass of cells is formed, which shows almost com- 
pletely the form of the young animal. f Morbid produc- 
tions assist in throwing light upon this point of inquiry. 
Valentin has observed in carcinoma a cell containing two 
others, each provided with a nucleus. J. Muller has 
witnessed young cells enclosed in older ones in cases of 
medullary sarcoma and some other cancerous affections. 

In healthy tissues the same experience exists, for ex- 
ample, in the formation of cartilage and in the growth of 
glands. The granules of mucus are nucleated cells; those 
of pus and lymph also. Schultz was the first to discover 
that the blood discs or corpuscles, are of the same de- 
scription, the matter which gives them a colour being 
contained within them.| 

In the vegetable kingdom young cells are generated 

* Encycl. Anat., p. 172, vol. vi. t Id. p. 173. t Muller, Physiol., p. 1614. 



ELEMENTARY CELLS. lxXV 

by partitions traversing the interior of the older cells : 
the divisions which occur in the interior of the yolk of an 
egg are considered as an analogy in the animal king- 
dom, to this process, though with that exception, the ex- 
amples are deficient. 

As each tissue of the body can produce cells of an as- 
similated nature to itself, so when accidents occur to such 
tissues, as in the case of a ruptured bone or muscle, the 
ruptured ends take on a similar action for the repair of 
the accident. The proceeding is modified according to 
the tissue ; if, however, in those accidents the ruptured 
ends be kept too far apart, the action does not extend to 
a sufficient distance, and the cure is incomplete, the in- 
termediate substance not conforming to a proper nature. 
In most instances common cellular substance supplies 
the deficiency. It is under this law that Henle has as- 
serted that light and repeated congestions are followed by 
simple hypertrophy, as in the muscles and epidermis, 
while greater congestions produce degeneration, indura- 
tion, and suppuration. 

In the early state of the foetus we find nothing but 
cells. They are held together by a substance which is 
called hyaline from its resemblance to glass, that is, being 
smooth, shining, destitute of fibres, and exactly homo- 
geneous in its appearance. Occasionally this intercellular 
substance is granular or even filamentous. The cells 
themselves in the ulterior development of the being, un- 
dergo for the most part metamorphoses which finally 
bring them into the condition of the several tissues enu- 
merated at the beginning of this treatise, as representing 
the classification of Bichat. Some of the cells retain, 
however, permanently their original character. The 
formation of cells is though, as previously remarked, not 
limited to any period of life, but is constantly going on, 
as these minute organic bodies are interposed in all the 



lxxvi HISTOGENY. 

functions of life, being involved in the secretions, con- 
nected with nutrition, found floating in numbers in all 
the assimilated fluids, and participating largely in inflam- 
matory actions. 

One might infer from the simplicity of this inceptive 
step of an organized being, that is, the presence of a mere 
cell from which others are generated, either internally or 
externally ; that wherever an organic compound, as pro- 
tein, or any of its cognates existed, there would be a 
spontaneous evolution of animal life in it, without the aid 
of fecundation. This opinion has in fact had numerous 
supporters and is not destitute of advocates at the present 
day; but the progress of knowledge is revealing con- 
stantly so many exceedingly minute forms of animal and 
of vegetable life, that it leaves as the strongest ground of 
inference, that in all cases of apparently spontaneous 
generation, ovula have been invisibly deposited in and 
around the matrix. Moreover, recent experiments show 
that neither vegetation nor animalcular evolution will be 
exhibited in fluids which have been subjected to such 
processes as must inevitably kill any germs which may 
have been deposited in them. 

From the state then of nucleated Cells, as described in 
the foregoing pages, all the tissues may be traced as they 
exist in the perfect and mature animal. The metamor- 
phoses of the cell, are found to have affected both its walls 
and the nucleus. 

In some instances the cells continue independent of 
each other, there being no disposition to coalesce ; this 
habit is remarked in the case of the circulating fluids 
as in the corpuscles of the blood, in those of the lymph and 
the chyle: in the epidermis, some pigment membranes, 
and the fat cells. In certain cases such cells grow largely; 
for example, a young elementary fat cell will be found at 
first only the ruVo of a line in diameter and subsequently 



cilia. lxxvii 

grows to be the 4 ^ 5 of a line. The shape of cells is also 
modified very much by pressure, some are flattened, some 
are pentagonal or hexagonal, some cylindrical, some pris- 
matic, some cuneiform or conical. 

A very singular metamorphosis of certain cells is where 
they produce at one side, or at various points, small 
thread-like elongations or fringes, called Cilia from their 
resemblance to the eye lashes. Such fringed cells are 
generally flattened whatever may be their shape beside, 
as pentagonal, cylindrical, or conoidal ; and are placed 
upon free or non-adherent surfaces. 

These Cilia, according to Purkinje and Valentin, are 
flattened, their points being rounded off; some are fusi- 
form ; and their length is from about j— to jzItq °f ari 
inch.* They are disposed in rows of some regularity. 
During life, and for some time after its extinction, they 
have a sensible waving motion, resembling that of a field 
of wheat agitated by a steady breeze, each one bending 
forwards and back again, and having also a gyratory mo- 
tion. The action of the cilia produces a current in the 
fluid contiguous to them, the course of which may be ren- 
dered very plain by mixing with the fluid, particles of finely 
powdered charcoal. The integrity of the cells, to which 
the cilia belong, is essential to this motion; for if they 
become dry or altered by putrefaction or chemically, the 
cilia cease to play. The scrapings of the throat of a frog 
are well suited to this display of epithelial ciliary motion. 
On one occasion, the latter was seen to last for seventeen 
hours, in a frog. In a turtle's mouth, it was found to last 
for nine days after decapitation ; in the trachea and lungs, 
for thirteen days, and in the oesophagus for nineteen days.f 
It appears to be entirely independent of muscular motion, 
as the removal of the brain and spinal marrow in frogs 
does not affect it, neither does the administration of hy- 

* Miiller's Physio]., p. 859. 

t Todd and Bowman, Physiol. Anat. p. fi2, London, 1843. 

Vol. I. — h 



lxXViii HISTOGENY. 

drocyanic acid, opium, strychnine, belladonna, or elec- 
tricity. 

This phenomenon exists to a great extent in the animal 
kingdom. In man it has been observed upon the surface 
of the ventricles of the brain and upon the choroid plexus, 
upon the Schneiderian membrane, the soft palate, the 
pharynx, the Eustachian tube, extending to the cavity 
of the tympanum, upon the lining membrane of the fron- 
tal sphenoidal and maxillary sinuses ; upon the lachry- 
mal passages, upon the lining membrane of the larynx, 
trachea and bronchial tubes, upon the lining membrane 
of the uterus and of the Fallopian tubes. 

To resume in regard to the metamorphoses of cells, 
they have a faculty of thickening their own walls, which 
is very perceptible in the cylindrical epithelial cells of 
the intestinal canal, and in the cells of cartilage. Such 
cells as are thickened by a deposite of internal stratifica- 
tions, present a striated appearance in their progress ; 
and, in certain cases, the cell is entirely filled, becomes 
flattened and solid, and all distinction is lost between its 
parts, as occurs in the upper layers of the epithelium. 

Another phenomenon attending the life of cells is their 
rupture or dehiscence and final disappearance. The cor- 
puscles of the lymph and of blood are considered as ex- 
amples of this. In the blood disc upon the absorption of 
its nucleus, the investing membrane thins down, is more 
easily destroyed by chemical agents as it grows older, 
and finally ends by being dissolved wholly. The cells 
of glands, commonly called mucous granulations when 
they are evacuated whole, undergo the same process 
naturally. The dehiscence or partial destruction of cells 
makes them enter into free communication with other 
cells, or with the surface of the body; or with the cavi- 
ties, being excretory ducts or otherwise, with which 



UNION OF CELLS. lxxix 

they are connected. It is said that such a dehiscence 
gives to the peripheral ends or origins of excretory- 
ducts, as in the salivary glands and mammae, their glo- 
bular termination. 

Cells are blended with contiguous ones by several 
modes of union. In one mode, their walls being thick- 
ened as explained above, they coalesce with adjoining 
cells similarly circumstanced, and with the intercellular 
substance, the cytoblastema : the cavities of the cells re- 
maining all the time separate. Henle thinks it to be on 
this principle that ossific cartilages are developed ; con- 
sequently, the bones themselves and the cement of the 
teeth. 

In another mode of union, the cavities of the cells com- 
municate freely, in consequence of the removal of their 
parietes where they come into contact. In some instances 
they make a continuous tube in that way, from several of 
them being in the same line. In other instances they 
are so grouped as to form a cluster of communicating 
cells. In other instances still, they are branched so as 
to make radiating communications. 

There are several points of a very minute character con- 
nected with the development and transition stages of cells, 
and of their nuclei into tissues: such as their fusion with 
each other, their metamorphoses by the reception of the 
ingredients or organisms of the tissues respectively, and 
also their evolution into filaments and canals. The de- 
tails cannot be very conveniently introduced on the pre- 
sent occasion, but they are subjects of deep interest and 
curiosity ; for an exposition of which see the General 
Anatomy of the Tissues under their respective heads, 
and also the same by a very careful and distinguished 
observer, Professor Henle, in his work on the History of 
the Tissues.* 

* Encycl. Anat., Pa- is, 1843. 



1XXX HISTOGENY. 

The foregoing observations on the primordial cells of 
the human body have their value established by the cir- 
cumstance, that the nutrition of a part consists in the 
growth of individual cells. The latter derive their nutri- 
ment from the organic compounds supplied by the blood, 
each set of cells making its selection upon the principle 
of a special affinity, for some particular constituent of 
that fluid. Every cell is therefore, to be considered as 
participating in the phenomena of life and of organization, 
by the influence which it exercises in its place. The 
modification of vital force, or the character precisely of 
that force, constitutes the problem of life, which, in the 
present state of the human mind, must be inexplicable. 
It is, indeed, an ultimate fact of Physiology, of an inscru- 
table character, an endowment of matter too subtle for 
human investigation. 



SPECIAL 

ANATOMY AND HISTOLOGY. 



BOOK I. 

PART I. 

OF THE SKELETON. 

The skeleton is the bony frame-work of the human body; and, 
by its hardness and form, retains in proper shape the whole fabric ; 
affords points for the attachment of muscles ; and protects many of 
the viscera. Anatomists call the bones, along with their natural 
connexions of ligaments, cartilages, and synovial membranes, a 
natural skeleton ; and the bones only, but kept together by artificial 
means, an artificial skeleton.* 

The bones are inflexible, and in a recent state are of a dull white 
colour, familiar to most persons from its being the same in animals ; 

* See Figs. 1, 2, 3, Anatomical Atlas, &c, by Henry H. Smith, M. D., 
Phila., Lea & Blancbard, 1844. The appropriateness of the selections of 
Plates for the above work, from the best authorities; and the fidelity of their 
execution by the Artists employed, claim for it my highest confidence: and it 
is, therefore, recommended as a most useful auxiliary to the Course of Anatomy, 
delivered in the University of Pennsylvania. The Publishers deserve the 
greatest credit for the unsparing liberality with which it was executed; and 
which has placed it incomparably in advance of any efforts in this country to 
rival it. Many of the figures are from preparations made by the author of the 
present work in illustration of his own dissections. The subsequent references 
to it will be simply as Anat. Atlas. 

Vol. I.— 7 



74 



SKELETON. 



but they are made of an ivory whiteness by being properly mace- 
rated and prepared. 

The regional division of the skeleton is into Head, Trunk, Supe- 
rior or Thoracic, and Inferior or Abdominal Extremities. 

If a vertical plane be passed from the top of the head downwards, 
through the middle of the skeleton, this plane will divide the latter 
into bilateral, or two equal portions, called, in common language, 
the right and the left side of the body. These two sides are per- 
fectly alike in shape and size.* Some of the bones are found in 
this plane, being intersected by it into two equal parts or halves : 
others are somewhat removed from it, and are in pairs. This ar- 
rangement antagonizes the two sides of the body, and qualifies it for 
all its motions. 



CHAPTER I. 
Histology of the Bones. 

SECT. I. NUMBER, TEXTURE. 

The number of the bones is commonly the same in every person 
of middle age ; but they are less numerous then, than in infancy, 
from several of them having been originally formed in pieces which 
coalesced afterwards. The farther fusion in advanced life, of con- 

* The exact harmony or symmetry of form and size, between the two sides 
of the body, as a general rule, is rather hypothetical than real in nature. It is 
a point of general notoriety, that the right side enjoys more force than the left, 
and this will be found attended with greater development. There are few 
persons that have not the face and the spine somewhat out of shape from the 
bones on one side growing larger than on the other, the right, commonly, pre- 
vailing over the left: hence we see a nose somewhat turned; and a spine 
curved, the convexity of which is to the right side, with the attendant conse- 
quences, on the position of the ribs — the scapulae and the sternum. This 
condition of false growth is exhibited in all degrees, from a deviation almost 
imperceptible to one amounting to deformity. The left side is said, also, to be 
more liable to diseases. Copious reports on these several subjects as well as 
on human stature, generally, at all ages, have been made by the French Anato- 
mists; for a summary exposition of which, see Malgaigne, Anat. Chirurg., 
Vol. I. Chap, 1. Paris, 1838. 



SITUATION OF BONES. 75 

tiguous bones into each other, diminishes still more their number. 
It is, however, generally agreed to view the following as distinct : — 

For the Head — An occipital bone, a frontal, a sphenoidal, an 
ethmoidal; two parietal; two temporal, each containing the small 
bones of the tympanum ; two superior maxillary, two palate, two 
malar or zygomatic, two nasal, two unguiform or lachrymal bones, 
two inferior turbinated, a vomer, and an inferior maxillary : 

For the Trunk — Twenty-four true or moveable vertebrse, one 
sacrum, four caudal vertebrse or bones of the coccyx, two innomi- 
nata, twelve ribs on each side ; a sternum, in three pieces, however, 
in the youthful adult : 

One hyoid, in three pieces, sometimes five in the adult, and situ- 
ated in the throat : 

The remaining bones compose the limbs, and are, therefore, in 
pairs, or correspond exactly on the two sides of the body. The) 
are, 

For the upper Extremities — The clavicle, the scapula, the os 
humeri, the radius, the ulna, the eight bones of the carpus, the five 
bones of the metacarpus, the two phalanges of the thumb, the three 
phalanges of each of the fingers, the two, and sometimes more, 
sesamoid bones : 

For the lower Extremities — The os femoris, the tibia, the fibula, 
the patella, the seven bones of the tarsus, the five of the metatarsus, 
the two phalanges of the big toe, the three phalanges of each of the 
smaller toes, and the two, sometimes more, sesamoid bones. 

There are, therefore, twenty-two bones to the head, not including 
those of the tympanum; fifty-six to the trunk of the body; one in- 
sulated bone to the throat ; sixty-eight to the two upper limbs ; and 
sixty-four to the two lower limbs. In all, tw r o hundred and eleven. 
The redundancy or the deficiency of the sesamoid bones, in a subject, 
may cause this number to be slightly increased or diminished. 

The situation of the bones varies ; some are profound, w'hile others 
approach very near to the surface of the body. They are, as stated, 
either symmetrical, — that is, consist of two lateral portions precisely 
alike; — or else in pairs, having a perfect correspondence with each 
other. The symmetrical or bilateral bones are the frontal, the occi- 
pital, the sphenoidal, the ethmoidal, the vomer, the inferior maxillary, 
the hyoid, the spinal, and the sternal; and they are situated under 



76 



SKELETON. 



the middle vertical line of the body. The pairs are on the sides of 
the middle line, more or less removed from it. 

The long bones (ossa longa) are those whose length prevails in 
great excess over their breadth, they are generally cylindrical or 
prismatic, and have their extremities enlarged for the purpose of 
articulating with adjoining bones. The broad bones (ossa lata) are 
those whose breadth and length prevail largely over their thickness, 
they have their shapes diversified by muscular connexion and by the 
forms of the viscera they contain. The thick bones (ossa crassa) are 
such as have their several lines of measurement more nearly of a 
length; they are situated in the vertebral column, and in the hands 
and feet; and have their surfaces very irregular. 

The bones present, on their periphery, eminences and cavities, a 
proper knowledge of which, is of the greatest importance to the 
surgeon. The former are called apophyses or processes, and are 
extremely numerous and diversified : they serve for the origin and 
insertion of muscles, and for furnishing articular faces. The cavities 
are also numerous \ some of them are superficial, and serve for arti- 
cular surfaces; others for the origin of muscles; for the enlargement 
of other cavities, as that of the nose and ear ; and for purposes which 
will be mentioned else\vhere. 

The articular ends of the long bones are called Epiphyses, from 
their being formed from distinct points of ossification, whereas, the 
shaft of the bone is its Diaphysis or body, being the part first formed. 
The epiphysis, therefore, as its name implies, grows upon the other. 
Many processes grow after the manner of epiphyses, from distinct 
points of ossification, though they are seldom called by the same 
appellation. This is the case with the trochanters of the os femoris, 
with the processes of the vertebrae, the crista of the ilium, and the 
tuber of the ischium. 

Near the centre of some bones a canal is formed which passes in 
an oblique direction, and transmits blood-vessels to their interior. 
There are also, at the extremities of the long bones, at the different 
points of the thick ones, and near the margins of the flat ones, a great 
many large orifices, which principally transmit veins: in addition to 
which, a minute inspection of any bone whatever, will show its 
whole surface studded with still smaller foramina, also for the pur- 
pose of transmitting both kinds of blood-vessels. 

The density of bones is always well marked, and exceeds much 



TEXTURE OF BONES. 77 

that of other parts of the body. It is, however, variable in different 
bones, and in different places of the same bone : hence their sub- 
stance has been divided into compact and cellular, of which the for- 
mer is external and the latter internal.* 

The Cellular structure^ or substance, grows from the internal sur- 
face of the other, and is composed of filaments and small laminae, 
which pass in every direction, by crossing, uniting, and separating. 
The cells, resulting from this arrangement, present a great diversity 
of form, size, and completion. They are filled with marrow, being 
hence called medullary cells, and communicate very freely with each 
other. The latter may be proved in the boiled bone, by the practi- 
cability of filling them all with quicksilver from any given point; 
and, indeed, by the injection of any matter sufficiently fluid to run. 
The communications between them are formed by deficiencies in 
their parietes, after the same manner that the cells of sponge open 
into each other. This structure does not exist in the earliest periods 
of ossification, when the bones are cartilaginous almost entirely, but 
develops itself during the deposite of calcarious matter. The man- 
ner of its formation is imperfectly understood, though it may possibly 
be the result of absorption, and it is not completed in the bones, 
originally consisting of several pieces, till these are consolidated into 
one. 

The Compact substance is also formed of filaments and laminae, 
which we find to be so closely in contact with each other, that the 
intervals between them are merely microscopical in the greater part 
of their extent : they become, however, more and more distinct, 
and larger, near the internal surface. And at the extremities of the 
long bones, the compact tissue is gradually blended with the cel- 
lular structure, or lost in it. Its filaments are directed longitudinally 
in the cylindrical bones, radiate from the centres of the Jlat ones, and 
are so blended as to render it impossible to trace them in the thick 
ones. This disposition in the flat bones is much better seen in early 
life : subsequently, it becomes indistinct. 

The compact and the cellular structure present themselves under 
different circumstances in the three species of bones. The compact 
has a predominant thickness in the bodies or diaphyses of the long 
bones, and is accumulated in quantities particularly great in their mid- 
dle, which, from its position, is more exposed than their extremities, to 

* Anat. Atlas, Figs. 3, 5. f Id., Fig. 4. 



"78 SKELETON. 

fracture from falls, blows, and violent muscular efforts. But as this 
texture approaches the extremities of the long bones, it is reduced to 
a very thin lamina, merely sufficient to enclose the cellular structure 
and to furnish a smooth articular face for the joints. The cellular 
structure, on the contrary, in the long bones, is most abundant in 
their extremities, constituting their bulk there, and is least so in their 
bodies. It is so scattered at the latter place, as to leave a cylin- 
drical canal in their middle, almost uninterrupted for some inches. 
This canal, cellular in its periphery, has its more interior parts tra- 
versed in every direction by an extremely delicate filamentous bony 
matter, which, from the fineness of its threads and the wide intervals 
between them, has been, not unaptly, compared to the meshes of a 
net, and is, therefore, spoken of especially under the name of the 
reticulated or cancellated structure or tissue of the bones, in contra- 
distinction to the cellular. It is formed on the same principle with 
the latter : and though the term, from that circumstance, has been 
rejected, upon high authority, as superfluous, it appears worthy of 
retention, as it expresses a fact of some importance. Too weak to 
contribute in an appreciable degree to the strength of the bone, the 
reticulated or cancellated tissue seems principally useful in support- 
ing the marrow and in giving attachment to its membrane. The 
extremities of this cylindrical canal gradually disappear by becoming 
more and more cellular. 

In the flat bones, the compact structure forms only their surface 
or periphery, and is of inconsiderable but generally uniform thick- 
ness ; the space within is filled up with the cellular structure, which 
is rather more laminated than it is in the long bones. 

In the thick bones, the compact structure forms their periphery 
also ; but, generally, it is thinner than in the flat : their interior is 
likewise filled up by the cellular structure, and does not present dif- 
ferences of importance, from the ends of the long bones. 

The lamellated state of bone is rendered more evident under the 
use of the microscope. In the long bones this lamellated structure 
is concentric in circles — but in the flat there is simply a superposi- 
tion in parallel plates. 

The compact tissue, particularly in the cylindrical bones, has 
in it a multitude of longitudinal canals, visible to the microscope, 
and some of them to the naked eye, which contain vessels and 
medullary matter. Those canals, originally described by Clopton 



TEXTURE OF BONES. 79 

Havers,* run parallel with one another in the spaces between the 
lamina?, and give off small branches which pass through one or 
more lamina?, and anastomose with contiguous Haversian canals, 
thus forming a reticulated communication of osseous tubes which 
permeate the compact substance. f They open externally and re- 
ceive their blood-vessels from the periosteum, and internally merge 
into the cells of the cellular structure, from whose medullary mem- 
brane they likewise receive blood-vessels. Some of them are as 
large as the j$v of an English inch, others as small as z ? W. And 
they are about tzc of an inch apart. They are, according to M. 
Beclard, about one-twentieth of a line in diameter, on an average ; 
but they are, generally larger near the interior than the exterior sur- 
face of the bones, and have frequent lateral communications with 
the cellular structure, and with the external surface. 

As the Haversian canals are common to all bones, they are uni- 
formly found formed of concentric circular laminae and ending in- 
ternally in the cellular structure. They are in fact miniature or ex- 
tremely attenuated representations of what the great medullary canal 
is in the long bones, and seem to execute very much the same func- 
tion in the accommodation of blood-vessels and fat. With their 
corresponding concentric lamina? each one is therefore a miniature, 
or subordinate bone, which for the advantage of a name may be 
called the Haversian Ossicle. As these vascular channels are very nu- 
merous, they therefore form a very fine net- work of canals in the 
midst of the compact substance. The arteries and veins which oc- 
cupy them are disposed to keep apart, each set of vessels having its 
own canals ; at least this is to a considerable extent the case ; a very 
strong example of which is seen in the venous diploic sinuses of 
the bones of the head, and in the bodies of the vertebra?. The inte- 
rior of a Haversian canal is lined by a layer of compact substance, 
and exterior to this layer is the concentric series of other layers in a 
variable number, from four to twelve or more, according to Henle| 
and others. The concentric condition is, however, not absolute, as 
the layers run here and there into one another, owing to the arrange- 
ment of the corpuscles of Purkinje. From the great number of 
the longitudinal Haversian canals, a long bone, when tested by a 

* Osteologia Nova, An. 1729. 

f Anat. Atlas, Figs, 8, 9, 10- 

^ Histoire des Tissues, Tome 2d, p. 397. 



80 SKELETON. 

microscope, seems to be formed in its compact texture almost 
wholly by them, so that it is really a fascis or bundle of the little stems, 
or ossicles forming the Haversian system, comparable to a bunch of 
the barrels of quills. 

The cancellated and the cellular structure are themselves a more 
expanded developement of the same arrangement. 

Microscopic excavations of a different description and called cal- 
cigerous also exist in bones. They are brought into view by ex- 
amining a transverse section of bone ground extremely thin and then 
polished. They consist in cells (Corpuscula Purkinje) from which 
radiate in every direction exceedingly fine tubules, (Tubuli Calci- 
geri, or Calciphori) which again send out branches, to anastomose 
with corresponding branches of similar adjoining cells. The term 
calcigerous is applied to this system from the belief that the calca- 
rious matter of bones is deposited in them.* Under a microscope 
which magnifies from two to three hundred diameters, some very fine 
striee, like the radii of a circle, in great numbers are found diverging 
in straight lines from the circumference of the Haversian canals to 
the circumference of the little cylinders of bone forming them, pro- 
truding through and through their laminae. f They are called the 
canals of Deutsch and should not be confounded with the corpuscles 
of Purkinje and their calcigerous tubes. 

The Corpuscles of Purkinje and their stellate branches appear now 
to be viewed by anatomists, as a very beautiful arrangement of small 
lenticular or flattened oval excavations in great numbers with their 
radiating tubules, anastomosing with those of adjacent similar exca- 
vations. A granular matter is found within them and their branches. 
The tubules take their origin from the interior of the Haversian 
canals, according to Mr. Tomes, ^ and pass in series between the 
canals, connecting them one with another. They then reach the sur- 

* The corpuscles of Purkinje, called after their discoverer, are among' the 
most permanent of the anatomical traits of bone, notwithstanding their extreme 
minuteness. In the petrified vertebra of a Zeuglodon (whose remains abound 
in the limestone of Alabama) sent to me by Dr. Alonzo B. C. Dossey, the 
corpuscles were exhibited in great abundance and very distinctly with the mi- 
croscope by my late assistant Dr. Joseph Leidy. This race of animals havin<r 
a length of about seventy feet, has been named by Professor Owen from the 
transverse section of the teeth, being in some degree a resemblance to the out- 
line of an hour-glass, and is considered as cetaceous by him instead of saurian 
as originally suggested by Dr. Harlan. Being found uniformly in the fossi- 
lized state, its antiquity defies human computation. 

f Anat. Atlas, Fig. 11. 
[ % See Physiolog. Anat. Todd, and Bowman p. 109. 



TEXTURE OF BONES. 81 

face of the bone, and end on it by open orifices, or are reflected 
back into the tissue of the bone, to enter the tubules adjoining. 

The proof of this system being permeable, is that if a dry section 
of bone in which they are very visible, be touched with a drop of 
oil of turpentine, this fluid -will penetrate quickly into the Haversian 
canals, from thence into the stellate tubules, thence into the lenti- 
cular excavations; thence through the tubules on the other side, and 
so on from one set to another till all be filled. When air has pre- 
occupied these spaces, and the turpentine can not displace it, the 
bubbles are very apparent. 

These lacunae have their flat sides for the most part in line with 
the nearest surface of bone. They have an average length of jsta 
of an inch, are about half as wide, and one-third as thick. The 
radiating tubules are from ^.W to rvJstns °f an mcn m diameter. 

The preceding exposiiion of the texture of all bones maybe sum- 
med up in the example of a long bone, which is, in itself, a good 
specimen of the arrangement every where else to be met with, un- 
der certain modifications. Upon the exterior periphery of the bone 
we see the surface occupied with an immense number of foramina 
for the transmission of vessels : upon the interior formed by the 
medullary canal, and the areolar structure, we have also great num- 
bers of orifices showing the vascular connexion of the medullary 
membrane, and, finally, in the intermediate compact structure, we 
have the bone made cribriform by the numerous microscopic chan- 
nels of the Haversian canals ; the canals of Deutsch ; and the lacunae 
and tubules of the Purkinjean system. It is estimated that these de- 
velopments of surface bring every point of bone within a small dis- 
tance, T ^ of an inch from a blood-vessel. 

My preparations; whatever may be said of other portions of bone, 
exhibit a layer derived directly from the external periosteum. In fact 
the latter is admitted now by the English Anatomists.* A similar 
layer they admit as derived from the medullary membrane, and form- 
ing the areolar structure. These two layers send out the osseous 
lining of the Haversian canal. As the lacunas or corpuscles of Pur- 
kenje are every where in the bone, their planes change their direc- 
tions, so as to observe that of the adjoining Haversian canals, and 
ossicles whether they be longitudinal, transverse, or oblique. 

If a thin natural plate of bone, as for example, a fragment of eth- 
moid, be examined microscopically, it is found not penetrated by 

* Todd and Bowman ut supra, p. 112. 



82 



SKELETON. 




blood-vessels, but is nourished simply from its surface by the vascu- 
lar periosteum there. Tested by prolonged boiling, so as to remove 
largely the animal matter, it is seen to consist of granules of osseous 
or calcareous matter, varying in size from the tjW to the *•«} <nr of an 
inch. A piece of this description exhibits the osseous tissue in its 

simplest state, and is dotted 
abundantly with the Purkinjean 
corpuscles sending out their stel- 
lated arms, which anastomose 
freely with others. The minute 
granular matter filling the cor- 
puscles is thought to have the 
faculty of drawing the nutritive 

Purkinjean Corpuscles magnified 500 , • i f ,i„ -i- • • t i n 

diameters;-*, central cavity : b, its ramifi- materials of the adjoining bbod- 

cations. vessels, by the intervention of a 

set of minute cells contiguous to the osseous tissue. A scale of some 
fish as, the Lepidosteus* which has no blood-vessels in it, exhibits a 
strong analogy with this arrangement in the human bone, there being 
an intertexture of canals like a net-work. The plates forming the 
cancellated structure of the thicker bones repeat the same exhibition, 
the nutritive matter being attracted into their substance from the 
Fig. 2. vascular membrane co- 

vering them. The radi- 
ating canals of Deutsch, 
which are like fine lines 
or filaments drawn from 
the Haversian canal of 
an ossicle to the cir- 
cumference of the lat- 

Section of a bony scale of the Lepidosteus; — a, show- ter, are formed by a 
ing the regular distribution of the Lacunce and of the -,- . „ , 

connecting canaculi ; b, small portion more highly * in eai Series Ot lacuna?, 

magnified. the longer diameters of 

which face inwards and outwards, and inosculate with those in 
the same line centrally and peripherally. Each lamina of the os- 
sicle is thus rendered porous ; and the ossicle may be described 
as a bone of itself, having for its centre a Haversian canal, con- 
taining a blood-vessel. As the corpuscles of Purkinje, and the 
radiating tubes of Deutsch communicate reciprocally, and connect 




* Carpenter, Elements of Physiology, &c, Phila. 1846. 



TEXTURE OF BONES. 83 

also with the canal of Havers, so every bone is formed largely 
of these systems of anastomosing tubes. The larger of which 
only, to wit, the Haversian, conduct blood-vessels, while the other 
being too fine for that purpose, transmit merely the nourishing juices of 
the bone, the sap we may say, derived from the blood. This arrange- 
ment of bone into canals compensates for its want of bibulous pro- 
perties like Cartilage, and the softer substances of the human body; 
and thereby secures to it an adequate degree of nourishment. 

As every round bone is thus formed from a fascis of Haversian 
cylinders or ossicles,* so the latter are held in groups by a cylinder of 
bone exterior to them all, and by another cylinder which is within, 
it being contiguous to the medullary ca*vity of the bone. The spaces 
existing between the contiguous Haversian ossicles are filled up by 
concentric lamellae of bone running in line with those of the external 
and internal cylinders.! 

A simple experiment on any of the cylindrical bones will prove 
that the tumefaction of their extremities does not add proportionately 
to their weight, as one inch or any other given section of the compact 
part weighs very nearly the same with a section of equal length from 
the cellular extremities. The swelling at the ends of the bones adds 
much to the safety of their articular union, as the extent of the sur- 
faces is thereby much increased, and, consequently, they are less 
liable to displacement. The cylindrical and the cellular cavities, 
thus formed in the long bones, by increasing the volume of the latter, 
add greatly to their strength beyond what would have occurred, had 
the same weight of material been solid. The late Dr. P. S. Physick 
demonstrated this most satisfactorily by a scroll of paper, which, on 
being rolled up successively, into cylinders of various sizes, has, like 
a lever, its power of sustaining lateral pressure on one of its extre- 
mities, continually increased as its volume or diameter is augmented, 
until the latter reaches a certain extent. The same highly distin- 
guished teacher also pointed out another very important advantage 
of the cellular structure. It is that of serving to diminish, and in 
many cases to prevent concussion of the brain, and of the other vis- 
cera, in falls and in blows. The opinion was verified by his demon- 
strating the momentum, which is communicated through a series of 
five ivory balls suspended by threads, when one of them is with- 
drawn from the others, and allowed to impel them by its fall. This 

* Anat. Atlas, Fig. 11. 

f Anat. Atlas, Figs. 8, 0, 10, 11. 



84 SKELETON. 

momentum is so completely transmitted through the series, that the 
ball at the farthest end is impelled almost to the distance, from which 
the first one fell. This familiar experiment, used as a preliminary 
test to the accuracy of his views, was immediately succeeded by his 
substituting for the middle one of ivory, a ball made of the cellular 
structure of bone. The same degree of impulsion now communi- 
cated at one end of the series, is almost lost, or rather neutralized, in 
the meanderings of the cellular structure of the substitute ; and par- 
ticularly if the latter be previously tilled with tallow or well soaked 
in water, so as to bring it to a condition of elasticity resembling the 
living state. 

In persons of advanced age, the marrow of the bones becomes 
more abundant, and their parietes thinner ; and we also observe then, 
that the bones break more readily, and are more crumbling, rotten, 
or soft, than during the anterior periods of life. In women, after 
the critical period is passed, these traits are especially developed, 
and the compact centres of the long bones have their texture more 
or less approximated to the spongy tissue. Mr. Velpeau* says, that 
in the amphitheatres of Paris, he has often cut easily with a scalpel, 
the ends of the femur, tibia, humerus, the bodies of the vertebras and 
the tarsal bones, when there was apparently no morbid lesion in the 
skeleton: a similar experience belongs to most practical anatomists. 



SECT. II. — COMPOSITION OF BONES. 

The bones under every modification of shape and mechanical ar- 
rangement, are constituted by precisely the same elementary matters : 
the principal of which are an animal and an earthy substance, in in- 
timate combination. Their minute analysis, according to Berzelius, 
when they are deprived of water and of marrow, affords 

32 Parts of gelatine, completely soluble in water ; 

1 Of insoluble animal matter ; 

51 Phosphate or rather subphosphate of lime ; 
11 Carbonate of lime; 

2 Fluate of lime ; 

1 Phosphate of magnesia ; 
1 Soda and muriate of soda. 

* Anat Chirurg. 



COMPOSITION OF BONES. 85 

There are some other ingredients manifested in the analysis of 
Fourcroy and Vauquelin, as iron, manganese, silex, alumine, and 
phosphate of ammonia. The relative proportions of the above in- 
gredients are not uniformly the same, as the bones of the cranium, and 
the petrous portion of the temporal in a remarkable degree, have 
more calcarious matter in them, than the other bones of the same 
skeleton. There is also a considerable diversity in individuals, 
according to their age and to certain morbid affections. 

Thus, according to Schreger* the bones of a child have one half 
only of earthy matter, while those of an old person have seven-eighths 
of the entire mass. 

The colouring of the skeleton by madder, when an animal is fed 
on it, is considered a sufficient proof of the phosphorus and calcium 
being in the state of phosphate of lime. 

Mullerf says, that his investigations have elicited the remarkable 
fact of the cartilage of bone before ossification, consisting of chon- 
drin, but afterwards of ordinary gelatin : and that bones affected 
with softening no longer yield gelatin, but contain a large quantity 
of fatty matter. 

The earthy matter gives to bones their hardness and want of flexi- 
bility, and is easily insulated from the other by combustion : which, 
in destroying the animal part, leaves the earthy in a white friable 
state, but preserving the original form of the bone. If the heat be 
of a high degree, the calcarious part becomes vitrified, and its 
cells are blended by fusion. The action of the atmosphere, long 
continued, also divests the bones of their animal matter, and the 
calcarious then falls into a powder. If the bones be kept beneath 
the surface of the ground, by which they are less affected by changes 
in temperature and moisture, the animal matter remains for an im- 
mense number of years. I have seen in the Hunterian Museum of 
London, preparations of the teeth of the Mastodon or Mammoth, in 
which the animal matter was exhibited entire, notwithstanding the 
great lapse of years since it was in a living state : and a repetition 
here of the same experiments on the teeth and bones of the same 
animal has exhibited the same result. I was also informed by the 
late Mr. Say, a distinguished naturalist, that animal matter has been 
detected in fossil shells, the existence of which was probably ante- 
rior to that of the human family. 

* Muller's Physiol, p. 393. f lb. p. 393. 

Vol. I.— 8 



86 SKELETON. 

The phosphoric acid of bones gives them a luminous appearance 
at night. Bichat says, that in these cases he has found an oily exu- 
dation on the luminous points, probably from the marrow or conti- 
guous soft parts. This phenomenon will account for many of the 
superstitions which in all ages have affected ignorant minds, on the 
subject of burying grounds. 

The immersion of a bone in diluted muriatic acid is the best me- 
thod of demonstrating the animal part in a separate state. The 
strong affinity of the acid for the earthy part, and the soluble nature 
of the salt thus formed, leave the animal matter insulated. In this 
state it preserves the original form of the bone, is cartilaginous, flex- 
ible, and elastic. The action of hot water alone, upon a bone, by 
continued boiling, will, from the soluble nature of the cartilage, se- 
parate the latter from the earthy part, and convert it into gelatin. 
The gelatin may be precipitated afterwards from the water by 
tannin. The mode of this combination of animal and of earthy 
matter is not understood, but it is generally supposed to exist by the 
extremely small cavities of the former receiving earthy particles, in 
the same way that sponge holds water.* 

From the unpublished researches of Mr. Tomes,f it appears that 
the ultimate structure of bone is granular. This arrangement is 
manifested both by calcination and by steeping in an acid. These 
granules are intermixed with the osseous lacume called the corpus- 
cles of Purkinje. 

There are no means for investigating the minute anatomy of the 
bones more instructive than the removal of the earthy part by an 
acid. The cartilage thus left is the complete mould, in every parti- 

* If we conceive the phosphate of lime and the other earthy materials of 
bone to be in a state of solution in the blood and serum with which the carti- 
laginous rudiment of thd bone is impregnated, any action which would preci- 
pitate the earthy materials, would also, of course, impregnate the cartilage 
with them, and this process may be considered as completed when the bone 
acquires its proper consistence. 

Considering cellular substance as the parenchyma or primordium of all 
other parts, it is probably a speculation not entirely groundless, that every pe- 
culiar tissue or o-landular texture has its elements precipitated from the circu- 
lating fluid in a manner analogous to that of the calcarious part of bone. This 
idea also affords a clew to a result almost uniform in protracted macerations of 
all tissues, to wit, the parts being brought back to the primordial state, by the 
peculiar deposites in them being dissolved in the water and removed. 

+ Physiol. Anat. &c, by Todd and Bowman, p. 108. London, 1843. 



COMPOSITION OF BONES. 87 

cular of form, into which the particles of calcarious matter were de- 
posited. In this state, the compact part of the bodies of the cylin- 
drical bones may be separated into laminae ; and these laminae, by 
the aid of a pin or fine-pointed instrument, may be subdivided into 
filaments or threads.* 

The lamina?, though enclosing one another, are not exactly con- 
centric. I have observed, that the more superficial come off with 
great uniformity and ease in the adult bone, but the intertexture con- 
tinually increases towards the centre. Bichat has objected to this 
dissection of the bones, that the laminae are not formed in nature, 
but factitiously, by the art of the anatomist, and that their thickness 
depends entirely on the point at which one chooses to separate 
them ; they, therefore, may be made thick or thin at pleasure. It 
does not appear to me difficult to account for the manner in which 
this laminated arrangement is produced. The longitudinal filaments 
of the bones adhere with more strength to each other at their sides 
than they do to those above or below, in consequence of which a 
plane of these filaments may be raised at any place and of any thick- 
ness. This fact does not involve the inference that the bones are 
originally formed by a successive deposite of one lamina over 
another ; it merely inculcates the mode of union between the fila- 
ments or threads. I am, however, inclined to the opinion that the 
periosteum secretes the external lamina? in the adult bone, inasmuch 
as they separate with unusual or peculiar facility from the subjacent 
one. We know that the periosteum has the power of this secretion, 
as a laminated deposite of bone on the roots of the adult teeth fre- 
quently met with, proves without doubt, as also the phenomena of 
necrosis. The vascular network of the periosteum is analogous or 
correspondent to that of the bone, for which reason it is that this 
membrane is one of the tributaries to the supply of bone in its grow- 
ing stage, but not in virtue merely of its fibrous character. The his- 
tory of the abnormal formation of bone in any one or all of the tis- 
sues of the body, is also a proof that wherever there are vessels it may 
in certain cases be secreted. 

The disposition of the cylindrical bones to separate into lamina?, 
is constantly manifested in such as are simply exposed to the atmo- 
sphere. 

The opinion of the laminated and filamentous arrangement of 

* Anat. Atlas, Figs. 6, 7, from preparations in Wistar Museum. 



88 



SKELETON. 



bones has been very generally received by anatomists. Malpighi, 
whose name is inseparably connected with minute investigations in 
anatomy, taught it. Gagliardi, also, in admitting it, thought he saw 
pins of different forms for holding the laminae together. Havers also 
saw the laminated and thread-like structure. In short, there are few 
of the older anatomists who have not adopted fully the opinion. 
Among the moderns, the late M. Beclard, the distinguished and 
able Professor of Anatomy in the School of Medicine in Paris, says, 
that when the earth is removed from bones by an acid, if they be 
softened by maceration in water, the compact substance, which pre- 
viously offered no apparent texture, is separated into laminae, united 
by filaments ; the laminae themselves, at a later period, separate them- 
selves into filaments; which, by a farther continuation of the process 
swell, and become areolar and soft. A long bone examined after 
this process, divides its body into several laminae, the most external 
of which envelops the rest ; and the remainder, by rarefying them- 
selves towards the extremities, are continuous with the cellular 
structure there. 

J. F. Meckel, of the University of Halle, has furnished the fol- 
lowing account in his General Anatomy of the Bones : — 

" The filaments and the laminae which constitute the bones are not 
simply applied one against the other, so as to extend the whole length, 
breadth, or thickness of a bone, or to go from its centre to the cir- 
cumference. They lean in so many different ways, one against 
another, and unite so frequently by transverse and oblique appen- 
dages or processes, that some great anatomists, deceived by this 
arrangement, have doubted the fibrous structure of bones. Never- 
theless, their opinion is not perfectly correct. In spite of those in- 
flections and anastomoses of fibres, the fibrous structure always re- 
mains very apparent ; and one is warranted in saying, that the di- 
mension of length exceeds the two others, in the texture of many 
bones. This predominance is chiefly well marked in the first periods 
of osteogeny ; for, at a later time, the fibres are so applied against 
each other, as scarcely to be distinguished. But these longitudinal 
fibres never exist alone ; there are many oblique or transverse ones 
from the first periods of ossification ; and they are even from the 
beginning so multiplied, that the number of longitudinal fibres does 
not prevail over them so much as at a subsequent period, when the 
fibres approach nearer, in such way that the transverse become 
oblique ; until at last, from the increase of the bone ; the latter at 



COMPOSITION OF BONES. 89 

first view, seems to be composed only of longitudinal fibres. The 
transverse and oblique fibres do not form a separate system ; but 
continue uninterruptedly with the longitudinal, which they unite to 
each other."* 

The venerable Scarpa, some years ago, advanced opinions ad- 
verse to the laminated and fibrous or filamentous tissue of bones, f 
The latter doctrine he was induced to think a mere mistake, arising 
from careless observation. Founding his own views upon what he 
had seen in the growing bone, in the adult bone when its earthy 
parts were removed by an acid, — and upon certain cases of disease 
attended with inflammation of the bone ; he denied, without reserva- 
tion, the existence of laminae and fibres in bones, declaring that 
even the hardest of them were cellular or reticulated. It appears to 
me, in looking over his paper, that a desire to overthrow old doc- 
trines and to establish new ones, has induced him to make one omis- 
sion in the report of his experiments, otherwise unaccountable in a 
man of his general intelligence and candour. Having softened the 
cylindrical bones in an acid, he next proceeds to a long continued 
maceration of them ; he finds, as other persons have done, the animal 
part of the bone finally resolving itself into a soft cottony tissue. He 
has made but one step from the immersion in the acid to the last 
stage of the process of maceration. Now, if in a short time after the 
bone had been softened in the acid, he had admitted an intermediate 
observation, he would no doubt, like all other inquirers, have found 
• that the animal part of the cylindrical bones was readily separable 
into laminae ; and that by a pin or needle these laminae could be 
split into fibres, the greater part of which are longitudinal; and that 
pounding the ends of these fibres with a hammer would resolve them 
into a very fine penicillous or brush-like structure. There is no ob- 
jection to the conclusion, that these laminae and filaments, as a final 
condition, produce a very fine microscopical cellular arrangement, 
which may be made more apparent in being distended by the de- 
velopment of gaseous substances, arising from putrefaction or mace- 
ration ; but there is reason for a decided opposition to the assertion of 
there being no fibres in bones, when we have daily under our eyes 

* Manuel D'Anat. Gen. Descr. et. Path, traduit de L'Allemand par Jourdan 
et Breschet. Paris, 1825. 

f A. Scarpa. De penitiori ossium structura commentarius. Leips. 1795. 
See also Anatomical Investigations, Philadelphia, 1824, by the late J. D. God- 
inan, M. D., for an English, translation of the same. 



90 SKELETON. 

preparations showing them ; some of which demonstrate the fibres 
running principally longitudinally, others spirally, like the grain of 
a twisted tree, and others having a mixed course. Upon the whole, 
the description cited from Meckel, exhibits this subject in a just and 
accurate manner. 

The more obvious arrangement of the cellular and compact struc- 
tures of the bones, indicates a considerable difference in their inti- 
mate texture : they are, nevertheless, closely allied ; for one structure 
is converted, alternately, into another by disease, of which specimens 
abound in the Wistar Museum. In both cases, from the fibres or 
filaments are formed cells which exist every where, and are only 
larger and more distinct in what we call the cellular structure ; but 
the compact part has also its cells, though they are smaller, more 
flattened, and for the most part microscopical.* 

Organization of Bones. — The blood vessels of the bones, though 
small, are very numerous. This is w T ell established, by the success 
of fine injections, which in the young bone communicate a general 
tinge ; and by scraping the periosteum from living bones, whereby 
their surface in a little time becomes covered with blood, effused 
from the ruptured vessels. In those operations for exfoliation from 
the internal surfaces of the cylindrical bones, where it is necessary to 

* The intimate structure of the bones, has been most carefully explored in mo- 
dern times, and our knowledge of it is very largely due to observations within a 
few years, as seen. At a former period, Havers had discovered the small canals, 
known now by his name ; and also, called medullary. Leeuwenhoeck had de- 
scribed the calcigerous canals, and the osseous corpuscles.* Gagliardif gave 
a good description of the lamellae, and filamentous arrangement of the bones. 
His observations were confirmed, and farther illustrated, by those of Duhamel^: 
and some others. Malpighi considered the bones as formed by a uniform net- 
work of flbres§ within the interstices of which, the calcarious elements were 
deposited, and he rejected the idea of a lamellar arrangement, except so far as 
it was artificially produced, by the manipulations of the anatomist. 

In regard to subsequent opinions on this point, Scarpa, as just stated, || re- 
jected the sentiment of the lamellar and fibrous condition of bones, and asserted 
that the bones consisted in a reticular cellular tissue, which in the flat and 
thick bones 13 perfectly homogeneous, the only difference between the spono-y 
and compact tissue being, that the latter is more dense in its structure than the 
other. 



* Anat. S. Inter. Eer. p. 2GJ..1C87. f Anal Os.». p J], an. 1689. 

X Acad, de Paris from 1730 to 1743. § Oper. posthmna, p. 47, an. 1697. 

I; De Penit. 0=s. StruM. 1799. 



OF THE VESSELS. 91 

excavate the bone extensively, in order to remove all the detached 
pieces; unless the general circulation of the limb be previously 
arrested by the tourniquet, the cavity of the bone is flooded with 
blood. Bichat has also remarked, that the blood vessels of the 
bones become unusually turgid and congested, in cases of drowning 
and strangulation. The observations in 1832, on cholera in Paris, 
showed the same congestion of black blood, to have been produced 
by that disease. 

The arteries which supply the bones, from their mode of distribu- 
tion, are referred to three classes. The most numerous and the 
smallest, are those which penetrate from the periosteum, by the capil- 
lary pores found over the whole surface of the bones. The next are 
those which penetrate the larger foramina at the extremities of the 
long bones, and at different points of the surface of others. And the 
third class, called nourishing, amounts to but one artery for each of 
the cylindrical bones and which penetrates by an appropriate canal, as 
mentioned, commonly near the centre of the bone. 

The arteries of the first two classes are generally extremely smalL 
They ramify upon the compact and cellular structure, penetrating 
it in every direction. At death, they are commonly filled with blood, 
which renders the injection of them difficult. The third or as com- 
monly called, the nutritious artery, is of a magnitude proportioned 
to the bone to be supplied. Being single in almost every instance, 
it passes through the compact tissue, and having reached the medul- 
lary cavity, it divides immediately into two branches ; each of which, 
in diverging from its fellow, goes towards its respective extremity of 
the bone. These branches ramify into countless capillary vessels 
upon the membrane containing the marrow,* and finally terminate 
by free anastomoses with the extreme branches of the two other 
systems. 

The veins of the bones are very abundant: they are found in com- 
pany with the branches of the third, or nutritious arteries, and their, 
common trunk goes out at the nutritious foramen into general cir- 
culation. These ramifications have been long known, and bring 
back the blood from the medullary membrane only. The veins 
which receive the blood of the other arteries do not attend them, and 
were first of all found in the diploic structure of the cranium, which 

* Would not this furnish a hint, that the arteries which secrete fat are dif- 
ferent from other arteries, and that this distinction may prevail generally? 



92 SKELETON. 

led to the discover}' of them in all the other bones. The honour of 
the original observation has been claimed respectively by two very 
distinguished men of Paris, MM. Dupuytren* and Chaussier.f 
These veins issue from the bones by numerous openings distinct 
from those furnishing a passage to the arteries. This circumstance 
is remarkably well seen in the flat and thick bones, and at the ex- 
tremities of the cylindrical ones. Having left the bone, they termi- 
nate, after a short course, in the common venous system. They 
arise exclusively from the spongy and compact structure, by ex- 
tremely fine arborescent branches, which, uniting successively, form 
trunks ; these trunks penetrate the compact tissue, and escape from 
the bone by orifices which are uniformly smaller than the bony 
canals of which they are the terminations. The canals are formed 
of compact substance, continued from the external surface of the 
bone, and are lined by the contained veins. The parietes of the 
canals are penetrated by smaller veins entering into the larger. M. 
Dupuytren is of opinion, that only the internal membrane of the 
venous system exists in this set of veins ; that it adheres closely to 
the bone, so as to be incapable of exerting any action upon the blood ; 
that it is very thin, weak, transparent, and is thrown into numerous 
valves. 

Lymphatic vessels are generally seen only on the surface of the 
bones. Mr. Cruikshank, however, on one occasion, while injecting 
the intercostal lymphatics, passed his mercury into the absorbents of 
a vertebra, and afterwards saw them ramifying through its sub- 
stance ;| a fact which, along with what is known of the power 
of exfoliation in bones, proves sufficiently the existence of such ves- 
sels in them. A few other anatomists as Soemmering, Breschet, and 
Bonamy lay claim to similar observations. The testimony of the 
former may be considered as going far to confirm the fact, as he has 
all along been admitted as one of the most accurate and cautious 
observers of modern times. The opinion is, however, rejected br- 
others of almost equal celebrity. 

Nerves have also been traced into the bones, accompanying for 
some distance the nutritious arteries on the medullary membrane, but 
there is no proof yet of nerves being distributed to the osseous sub- 
stance itself. § 

* Propositions sur quelques points d' Anatomie, Physiologie, &c. Paris, 1803- 
-f- Exposition de la Structure de l'Encephale. Paris, 1807.. 
^ Anatomy of Absorbing Vessels, p. 98. London, 1790- 
§ Beclard, Elemens d'Anatomie General^, Paris, 1823.. 



OF THE PERIOSTEUM. 93 



CHAPTER II. 

SECT. I. — OF THE PERIOSTEUM.* 

The membrane which surrounds the bones is called periosteum, 
and is extended over their whole surface, excepting that covered 
by the articular cartilages. As this membrane approaches the 
extremities of the bones, it is blended with the ligaments uniting 
them to each other, from which the ancients adopted the opinion, that 
the ligaments and periosteum were the same. Many fibres pass from 
the periosteum to the bone, by which it is caused to adhere. These 
fibres are more numerous and strong at the extremities than in the 
middle of the cylindrical bones ; also upon the thick bones, than 
upon the flat ones. The blood vessels of the bones accompany 
these fibres and contribute to the adhesion. The periosteum is 
united to the muscles and to the parts lying upon it, by cellular 
substance. 

The adhesion of the periosteum to the bones varies in the several 
periods of life. In infancy it maybe separated from them with great 
facility : in the adult it adheres more strongly in consequence of its 
internal face having taken on a secretion of bone, by which it is 
blended intimately with the bone it surrounds ; and in old age it is 
still more adherent, from the progress of its ossification. It is thick 
and soft in the infant, and becomes thinner and more compact as 
life advances. 

The organization of the periosteum is fibrous ; the fibres pass very 
much in the same direction with the fibres of the bones, excepting 
the flat bones, on which they are not radiated. These fibres have 
different lengths, the more superficial are longer, while the more 
deeply seated extend but a small distance. Inflammation develops 
the fibres in a striking manner, by occasionally making the membrane 
as thick as an aponeurotic expansion. 

The blood vessels of the periosteum are numerous, and can be 
easily injected. They come from the contiguous trunks, and ramify 

* Anat. Atlas, fig. 17. 



94 SKELETON. 

minutely, into a vascular net- work, many of whose branches pene- 
trate into the bone, and have the distribution already mentioned. A 
few lymphatic vessels have been observed in it. Its nerves have 
not been clearly discovered, though the sensation of extreme pain, 
when violence is done to it in an inflamed state, may be thought a 
proof of their existence. In health its sensations are null, or ex- 
tremely obscure.* 

The periosteum receives the insertion of tendons, of ligaments, 
and of the aponeuroses. In early life, owing to their slight attach- 
ment to the bones, all these parts may be torn from them, with but 
comparatively little force. Bichatf having advocated the opinion, 
that the internal laminge of the periosteum become ossified in the 
adult, considered that as a means by which all the fore-mentioned 
insertions into it were identified with the bones and thus accounted 
for the great degree of tenacity with which they adhere, and the im- 
mense force they are capable of sustaining, without being detached 
from their insertions. In this tendency to ossify, the periosteum 
manifests a great similitude to other fibrous membranes, as the dura 
mater, the sclerotica, and the tendons. 

The real state of the case is, that the periosteum does not insinuate 
itself as a distinct layer between such insertions and the bone. It 
ought rather to be said that the fibrous character which is in common 
to the periosteum — the animal part of bone — and the tendons, liga- 
ments, and aponeuroses is so uniform; that if a bone with these 
others attached is softened in an acid, it will be seen that there are 
no strict limits observed between them, but that these several textures 
run into each other, and have their filaments so continuous, that they 
have no lines of separation whatever, but are rather identified or 
blended, the one with the other, wherever an insertion or firm at- 
tachment is in question. 

The use of the periosteum is to conduct the blood vessels to the 
bones ; to protect the latter from the impression of the muscles, and 
other organs ; which come in contact with them ; to keep the ossifi- 
cation of the bones within its proper boundaries ; to give shape to 
them ; and to secrete bone in the growing state or in fractures ; and, 
finally, as has been suggested by the late Dr. Physick, it exerts a 

* Purkinje, it is said, has found a copious network of nervous filaments 
in the periosteum, 
t Anatomie Generale. 



MEDULLA, AND ITS MEMBRANE. 95 

very happy influence in turning from the bones suppurations in 
their vicinity, which would otherwise be pernicious to them. 



SECT. II. OF THE MEDULLA, AND ITS MEMBRANE, CALLED 

THE INTERNAL PERIOSTEUM. 

A greasy substance, as already stated, fills the cells of the bones ; 
it does not, in its composition, differ from common fat ; its granules, 
however, seem to be somewhat finer. From its resemblance in posi- 
tion to the pith of vegetables, it has obtained the name of medulla 
or marrow. It is contained in a very fine cellular and vascular 
membrane, lining the internal cavities of the bones, and, sending 
into their compact substance very delicate filaments. The existence 
of this membrane has been denied, but it maybe established by saw- 
ing a bone in two, and approaching the cut end to the fire, so as to 
melt out the marrow ; also, by digesting a bone for some days in hot 
spirits of turpentine, or by immersing it in an acid, in which cases 
the membrane becomes crisp and distinct. Its delicacy is so ex- 
treme, that it can only be compared to a spider's web. In this state 
it may be traced, lining the whole cylindrical cavity of the long 
bones, and extending itself to their extremities. It also exists in the 
diploic or cellular structure of all the other bones ; but it is scarcely 
possible to demonstrate it there in a very distinct manner, owing to 
its extreme tenuity. 

The medullary membrane is composed principally of the minute 
and numerous blood vessels spent upon the internal surface of the 
bones, aided by a very fine, soft, cellular tissue, merely sufficient in 
quantity to fill up the meshes between the frequent anastomoses of 
the vessels. From the latter cause, it is compared to the pia mater 
and to the omentum. It has been stated that its blood was derived 
from the nutritious artery, which communicates freely with the other 
arteries of the bones. This membrane is so arranged as to form along 
the course of the blood vessels small vesicular appendages which 
contain the marrow, and bear some analogy to a thick bunch of 
grapes, hanging from the several pedicles of the stem. 

Its nerves are extremely small ; they enter by the nutritious fora- 
men, and have been particularly observed by Wrisberg and Klint.* 

* Beclard, loc. cit. 



96 SKELETON. 

They have* not, as said, been traced ramifying in the substance of 
the bone, but follow for some distance the course of the principal 
arteries. 

With the exception of Mr. Cruikshank's solitary injection of a 
vertebra, no lymphatics have been observed satisfactorily on this 
medullary membrane ; and such lymphatic trunks of the external 
periosteum as are supposed to arise from the medullary membrane, 
have not been traced nearer to it, than the orifice of the nutritious 
canal. 

Some differences exist in the nature of the contents of the medul- 
lary membrane ; for example, that part of it which is reflected over 
the cells in the extremities of the long bones, and in the whole in- 
terior of the flat, and of the thick ones, contains a much more bloody 
and watery marrow, than what is found in the cylindrical cavities of 
the long bones ; the latter, indeed, resembles closely, as just stated, 
common adeps, presenting no essential differences from it. These 
circumstances have given occasion, without a material distinction of 
texture, to divide the medullary membrane into two varieties. 

That variety contained in the cellular extremities of the long bones, 
and in the spongy bones generally, is in a superior degree vascular. 
The part filling the meshes of its vessels is, however, so imperfect, 
that Bichat declared his inability to find it, and that the number of 
the fine vessels was what gave, fallaciously, the appearance of a 
membrane ; while, in fact, the intervals between them were large, to 
allow the fat to come into contact with the naked bone. The probability 
of this deficiency is confirmed by the difficulty of finding a mem- 
brane in the microscopical pores of the compact substance, yet the 
existence of fat in it is proved by its becoming greasy when insulated 
and exposed to heat. There may notwithstanding be extremely at- 
tenuated fat vesicles here as elsewhere with the existence of adeps. It 
is from the great abundance of blood in this variety of the medullary 
tissue, that the proportion of its adeps is small. 

The second variety of medullary membrane is displayed in the 
cells and in the cylindrical cavity of the diaphysis or body of the 
long bones. Its membranous cells communicate freely with one 
another, when the membrane is entire ; but according to the obser- 
vations of Bichat, not with such as are in the epiphyses of the bones ; 
and the line of demarkation is abrupt and well defined. This is 
proved by attempts to inflate the one from the other ; the air, in such 



DEVELOPMENT OF THE BONES. 97 

cases, passes with great difficulty. The texture of this medullary 
membrane, from its extreme delicacy in a natural state, is rather ob- 
scure, but it is occasionally well developed in disease. Its sensi- 
bility has not been very apparent in such cases of amputation as I 
have seen, though it is said, by some, to be extremely exquisite. 
In whatever degree the sensibility exists in different subjects, it is 
always more apparent in the middle than near the extremities of the 
long bones ; which may be accounted for by its nerves constantly en- 
tering at the nutritious foramen, and extending from thence towards 
the extremities. 

The fat in the humerus of the bullock, amounts to 96 per cent, of 
the medulla, and in very corpulent human subjects, cannot be much 
less ; it deviates much, however, from that proportion, according to 
the general state of health, until in extremely protracted diseases the 
adipose matter disappears, as in all other parts of the body. On the 
contrary, the medulla of the diploe, and cellular structure of all 
bones, makes a reddish, gelatiniform pulp, which, according to the 
analysis of Berzelius,* has scarcely a trace of fat ; it being composed 
of water, 75.5; and solid matters 24.5, identical with those elimi- 
nated from meat by water, as albumen, colouring matter, extract of 
meat, and the ordinary saline substances. 

The medullary membrane, besides its use in secreting the marrow, 
is highly serviceable to the nutrition of the bones, as proved in the 
experiments of Trojat, who, by destroying it, produced their death, 
and an artificial necrosis, which was cured in the usual way by a 
new secretion of bone from the periosteum. The marrow which it 
contains in the adult is not perceptible in the foetus. 



CHAPTER III. 
On Osteogeny. 

SECT. I. — OF THE DEVELOPMENT OF THE BONES. 

At birth, though the skeleton is sufficiently solid to preserve the 
shape of the individual, yet it is very imperfect in many particulars, 

* Traite de Chimie. t. hi. p. 486 

Vol. I.— 9 



98 SKELETON. 

which will be pointed out more in detail hereafter. At present it 
may be stated that the ends of all the long bones are mostly cartila- 
ginous* — the carpus and tarsus are nearly in the same state — the verte- 
bra?, true and false, have their processes very imperfect; and consist, 
each in several distinct pieces, united by the remains of the cartilaginous 
state. Several of the bones of the head are in the latter condition ; 
and the sutures are so imperfect that the flat bones readily ride over 
each other from the thinness of their edges, and also have the an- 
gles rounded, which occasions the vacancies called fontanels. 

From the early embryo state to the completion of the skeleton, 
three stages are observed in the progress of ossification ; the first is 
mucous or pulpy, the second cartilaginous, and the third osseous. 

I. The mucous stage is seen at a very early period after the embryo 
has been received into the womb, and presents itself under two 
modifications. In the one, from the general softness of the whole 
structure of the embryo, and from the apparently homogeneous 
nature of its constituents, the mucous rudiments of bone do not dis- 
tinguish themselves from the other parts : This condition, however, 
is soon changed into one, and that before the expiration of the first 
month of gestation, in which these rudiments assume a solidity and 
colour, which mark them olf, both to the eye and to the touch, from 
the still softer parts surrounding them. 

II. About the expiration of the first month the mucous stage is 
converted into the cartilaginous, and the consistence of the bones 
then increases continually by the accumulation of gelatine. Bichat 
makes a remark on this subject which has been confirmed by the 
experiments of Scarpa, though erroneous deductions have been made 
by the latter: that we do not see, during the formation of the carti- 
lages, those longitudinal strise in the long bones, radiated in the flat, 
and mixed in the thick bones, which distinguish the osseous state. 
The cartilaginous state presents another peculiarity worthy of obser- 
vation: all the bones which in a more advanced stage are to be 
united by cartilage, as the vertebras, those of the pelvis, and of the 
head, make, in their groups, respectively, but one piece ; while those 
which are to be united by ligament, and consequently to be moveable, 

* Anat. Atlas, Fig. 16. 



DEVELOPMENT OF BONES. 99 

as the femur, the tibia, the clavicle, and so on, are respectively in- 
sulated. In the cartilaginous state the bones have neither cells nor 
medullary cavities, and consist in a solid, homogeneous mass, the 
form of which is sufficiently definite ; and has its surface covered by 
periosteum* 

The flat bones of the cranium seem to be an exception to the 
general rule -of a preliminary cartilaginous state, and are commonly 
thought to be such. Their appearance is delusive, from the carti- 
lage being extremely soft and thin, and concealed by the pericranium 
on the one side, and the dura mater on the other ; but a careful dis- 
section enables one to distinguish it from this double envelope. f 

III. The osseous matter begins to be deposited when the rudi- 
ments of the bone have become entirely cartilaginous, with the 
exception of a few mucous points.:}: In certain bones this change is 
observable about the commencement of the second month§ after 
conception: J. F. Meckel has placed it about the eighth week. 
The colour of the cartilage first becomes deeper ; and, in the region 
where ossification is to commence, is of a well-marked yellow. The 
blood vessels, which before this carried only the transparent part of 
the blood, now dilate, so as to admit the red particles, and a red 
point is perceived, called the Punctum ossificatio7iis, from its receiving 
the first calcarious deposite. This deposite is always near the very 
centre of the cartilaginous rudiment, and not at its surfaee; the por- 
tion of cartilage nearest to it is of a red colour ; but, a little farther 
off, opaque and hollowed into canals. The ossification increases on 
the surface of the cartilage, and in its interstices, by continual de- 
posites, which are always preceded by that condition just mentioned. 
The canals of the cartilage transmit the blood vessels, and are large 
at the beginning of ossification ; but, as the process advances and is 
completed, they diminish gradually, and finally disappear. 

The cartilage of ossification, like the permanent cartilages, as the 
costal, the laryngeal, and some others, is composed of a semitrans- 
parent and somewhat fibrous or filamentous material. Immersed 
in this are numerous microscopic corpuscles or cartilage cells, flat- 
tened slightly and containing a nucleus or several granules. 

The absolute process of ossification begins by the deposition of cal* 

* Anat. Atlas, Fig. 12. f Bichat, loc. cit. 

% Anat. Atlas, Fig. 14. § Beclard, loc. cit. Bichat, loc. cit. 



100 SKELETON. * 

carious matter in the spaces of the semitransparent matter between 
these corpuscles. According to Dr. Sharpey,* these corpuscles had 
no definite linear arrangement previously, but upon the approach of 
the bony deposite they assume one, with their long diameter trans- 
verse, and they form in double or single lines, the ends of which 
look towards the ossifying surface. The bony deposite finally sur- 
rounds completely the cartilaginous corpuscles individually, and the 
latter themselves are transformed into bone,f as proved by muriatic 
acid, which removing the bone restores the appearance of the original 
cartilaginous corpuscles. 

It is asserted,^ that after the ossification of the spaces between the 
corpuscles or cartilage cells, the latter attach themselves to the ossi- 
fication or cancellous structure as it exists, and in being ossified them- 
selves their nuclei escape the process and finally become the lacunae or 
corpuscles of Purkinje, and that a new substance or blastema is formed 
in the cancelli, from which probably the vessels of the bone are 
developed for its future growth. The cancelli when first formed are 
closed cavities, but by farther development become Haversian canals 
and what they are in the perfect state. 

An extension of the preceding processes, with a corresponding 
development or generation of new cartilaginous corpuscles, finishes 
finally the complete fabric of the skeleton. 

The progress of ossification is somewhat modified in the three 
classes of bones. 

In the Long bones a small ring is observed to form early near their 
centre, and to be perforated on one side by the nutritious artery. 
This ring has its parietes thin, but broad, and its cavity is the begin- 
ning of the medullary canal. It is made of very delicate fibres 
which advance towards the extremities of the bone,§ and at the same 
time increase in thickness ; so that at birth, the body or diaphysis is 
generally finished. Commonly, at a period subsequent to birth, but 
differing in the several bones, their cartilaginous epiphyses also begin 
to ossify, by the development in their centre, of points of ossification 
which present the phenomena already mentioned. The cartilaginous 
state of the epiphysis gradually disappears by retiring from the arti- 
cular end of the bone towards its diaphysis; and, just before its 
complete removal, it appears as a thin lamina, gluing the end or 

* Miiller's Physiol, by Baly, p. 107. f Miescher de Infl. Oss. 183G. 

$ Todd and Bowman, p. 120. § Bichat, loc. cit. 



DEVELOPMENT OF BONES. 101 

epiphysis of the bone to its body. Several of the apophyses of the 
long bones are also formed from distinct points of ossification. 

The ossification of the Flat or Broad bones begins by one or more 
points, according to the bone being of a simple shape as the parietal ; 
of a double shape or symmetrical, as the frontal, where there are two 
points of ossification ; or of a compound shape, as the occipital and 
temporal, where there are several points. The commencement of 
ossification in them, is also manifested by the appearance of a red 
vascular spot in the cartilaginous rudiment, in which the osseous 
matter is deposited, and from which it progresses in radiated lines.* 
The periphery of this circle of rays presents intervals between the 
fibres, giving it the appearance of the teeth of a fine comb : these 
intervals are subsequently filled up by the sections of radii starting 
from them, and so on successively till the bone is finished. In the 
infantile head the several radii grow with a space nearly equal ; so 
that where the bones are angular, the angles being most distant from 
the centre of ossification are finished last of all, from which result the 
fontanels. Where the bones are intended to be kept distinct from 
each other, their fusion is prevented by a membranous partition ; but 
when they are to coalesce into one piece, only cartilage is found ber 
tween their edges, and which is subsequently ossified. 

In some of the flat bones, as the sternum and the sacrum, there 
are, first of all, a great many distinct points of ossification, which 
quickly unite into a smaller number ; they then remain stationary for 
a number of years, but finally all unite into but one piece. 

The ossification of the Thick bones begins by one or more points, 
according to the simplicity or complexity of their figures. The 
bones of the tarsus and of the carpus, have each but one point, while 
those of the spine have several. The former two, as stated, are 
almost entirely cartilaginous at birth. The remaining phenomena of 
ossification in these several bones are the same as has been men-* 
tioned. 

The centres of ossification show themselves at different times in 
the different bones. Gerberf considers the process to occur first 
about the sixth week in our larger domestic animals. The rotation 

* Anat. Atlas, Figs. 13, 18. f Genl. Anat. p. 187 

9* 



102 SKELETON. 



he lays down is first the vertebrae— then the lower jaw— next the os 
frontis— next the bones of the face. The middle portions of the ribs 
are ossified at an early date, and almost extemporaneously the larger 
bones of the extremities, the thoracic anticipating the abdominal. 
We next have the cylindrical bones of the hands and feet, and finally 
the carpus, the tarsus, and the patella, whose ossification begins 
somewhat before birth or shortly after. Messrs. Todd and Bowman* 
assert, meaning, as I understand it, the human subject, that the ossi- 
fication of the clavicle is the first, it commencing during the fourth 
wee k— the vertebrae and pelvic bones they set down as late. 

SECT. II. — ON THE MANNER IN WHICH BONES GROW. 

After the cartilaginous condition of the bones has been supplied 
by the complete deposite of osseous matter, and they are finished, 
with the exception of the epiphyses being fused into their respective 
bodies, the bones still continue to grow till the individual has reached 
a full stature. This is effected by the successive addition of new 
matter to the old. The long bones lengthen at their extremities; 
this is proved by the following experiment of Mr. John Hunter, f 
Having exposed the tibia of a pig, he bored a hole and inserted a 
shot into each extremity of the diaphysis ; the distance between the 
two shots was then accurately taken. Some months afterwards, when 
the animal had increased considerably in size, the same bone was 
examined, and the shots were found precisely at their original dis- 
tance from each other, but the extremities of the bone had extended 
themselves much beyond their first distance from the shot. The flat 
bones increase in breadth by a deposite at their margins, a cir- 
cumstance which has been known a long time, but it required the 
ingenuity of Mr. Hunter to prove conclusively that the long bones 
increase in length by a similar process, and not by interstitial depo- 
site, as Duhamel thought. This observation explains most satisfac- 
torily the use of the cartilage between the diaphysis and the epiphysis 
in all bones ; that it is preserved for forming new cartilage corpuscles 
and for the purpose of offering the least possible resistance to the new 
osseous fibres, which grow from the epiphyses and from the diaphy- 
ses : and that it is kept for this end, without any material change in 

* Loc. cit. p. 116. 

f Experiments and Observations on the Growth of Bones. Transactions of 
a Society for Improvement, vol. ii. London, 1800. 



GROWTH OF BOXES. 103 

thickness, from the fourth or fifth year to the sixteenth or eighteenth, 
when it disappears, because there is no longer any use for it, in 
consequence of the bones having attained their full length. 

The epiphyses are then manifestly intended to favour the elonga- 
tion of the bodies and the development of the extremities of the 
long bones, to meet the same purposes in some of the flat bones, as 
those of the pelvis, and to permit the general development of the 
bodies of the vertebra?. The ossification of the epiphyses com- 
mences in some bones about fifteen days before birth, as in the in- 
ferior extremity of the thigh bone, and in others, as those of the ossa 
innominata, not till the fifteenth year or thereabouts. Many of the 
processes from the bones, are also epiphyses, as the trochanters of the 
os femoris, the tuber of the ischium, the acromion scapula?, the seven 
processes of a vertebra, and so on, and are developed in the same way. 
The time at which they all are thoroughly fused into the bones to 
which they belong, extends from the fifteenth to the twenty-fifth year ; 
depending upon the individual bone, and upon varieties of consti- 
tution in different persons : though this process may be considered as 
completed, generally, in the female at the age of eighteen, and in 
the male at twenty-one. 

The increase in thickness of every bone depends upon a continued 
secretion from the internal surface of the periosteum, at first soft and 
mucous, then osseous : when this secretion is arrested, the bones 
cease to grow in thickness, which commonly occurs some time after 
they have attained their full length. The changes which subse- 
quently take place in them are those of interstitial deposite and ab- 
sorption ; the former is well exemplified in inflammation of the bones, 
and in spina ventosa ; the latter in the diminution of the bones in 
extreme old age, and in the loss of the alveolar processes. A species 
of interstitial growth is also now admitted to occur by the dilatation 
of the primary cancelli and of the Haversian canals. By the obser- 
vations of Mr. Tomes each of the latter is found in the experiments 
with madder to be deeply tinged with this substance.* 

There is great diversity of opinion in regard to the secretion of 
bone from the periosteum, in the growing stage. Mr. Muller, is so 
decided on this subject, that he says,f the idea that bones are 
formed by the periosteum, appears to him a barbarism unworthy 
of the present state of physiology. This he grounds upon the 
principle, that one organ in a part, cannot be the nutrient organ 

* Phys. Anat., by Todd and Bowman, p. 123, an. 1843. 
f Physiol, p. 408. 



104 



SKELETON. 



of another, therefore, the osseous substance being organized must 
assimilate to itself organized matter. This opinion, however de- 
cided, is strongly opposed by preparations in the Museum of 
St. Bartholomew's Hospital ; where in cases of necrosis, the shaft 
of the bone having died, there were plates of osseous substance on 
the inner surface of the periosteum. In experiments also by Mr. 
Stanley, a portion of the length of the bone being removed, the 
periosteum being left, the bone was reproduced, — but this latter, 
failed in a case where the periosteum was removed along with the 
portion of bone. Mr. Syme also obtained a secretion of bone from 
the under surface of the periosteum, where the latter had been kept 
raised and separated from the bone, by the introduction of a thin 
plate of metal.* Also in an ossification [osteophyte,) appended to 
the internal face of the dura mater, at the base of the falx cerebri, 
and belonging to the collection of the University of Pennsylvania, this 
production was found by a most careful and experienced observer, 
my then assistant, Dr. Joseph Leidy, to have, under the inspection 
of the microscope, the corpuscles of Purkinje and other characters of 
true bone. 

The following figure drawn from it by Dr. Leidy, is a true exhibit 
of its structure. 

There is no period of life in which 
the interstitial absorption and deposite 
is not continually occurring, but it 
is much more rapid in young and 
growing animals than in the adult and 
old. The experiments of Mr. Hunter 
and of Duhamel, show, that when a 
growing animal is fed upon madder, 
(rubia tinctorum,) owing to its affinity 
for phosphate of lime, the bones are 
quickly coloured by its being eli- 
minated from the blood; when the 
madder is withheld, the bones become 
again white ; and that the first appear- 
ance of the restoration of the latter 
is manifested by a white lamina being 
Successive layers of red and white bone 



Fig. 3. 




a Haversian ossicles. 

b Haversian canals. 

c Corpuscles of Purkinje. 

d Radiating- canals of Dculsch. 



deposited on their surface. 



Muller ut supra, p. 471, note by Dr. Baly. 



GROWTH OF BONES. 105 

may be thus formed. The madder, under such circumstances, is a 
long time in getting out of the bones. I fed a young pig for one 
month on it, mixed with other food. At the expiration of the suc- 
ceeding five'months, the animal, having grown very considerably, was 
killed. The interior lamina? of all the bones continued to be deeply 
tinged, while their surface from the deposite of new bone had be- 
come white. From this it would appear that deposite is a very 
permanent thing in bones ; it, of course, must prevail much over 
absorption, else their growth would be arrested. 

This effect of madder first observed by Belchier, and the result 
of the affinity between madder and phosphate of lime may be proved 
as follows, out of the body. No change occurs, when an infusion 
of madder is added to a solution of muriate of lime, but if a solution 
of phosphate of soda be added, a decomposition occurs in the two 
salts, and muriate of soda and phosphate of lime are then formed. 
The madder is immediately attached to the phosphate of lime, and 
the latter being insoluble, falls at once down as a crimson lake 
coloured precipitate. The colouring matter of the madder, when it 
is used as food, being introduced into the circulation, its union is 
thus established with phosphate of lime, and especially with that 
which is on the eve of being deposited in our tissues. 

In very young animals according to Mr. Tomes,* one clay is suf- 
ficient to tinge the entire skeleton, and in that case, the Haversian 
canals are each seen to be the centre of a beautiful crimson ring. 
In old animals, the process is much slower, owing to the points of 
bone being farther removed from the blood vessels, and therefore 
reached more slowly through the process of imbibition, which to 
some extent, must always take place in tissues not wholly vascular. 

At the same time that the periphery of each bone is increasing in 
its dimensions, the medullary canal is also augmenting : this arises 
from an absorption going on internally, while the deposite is making 
externally. Duhamelf proved this by a curious experiment. He sur- 
rounded a cylindrical bone of a young animal with a metallic ring ; 
on killing the animal sometime afterwards, he found the ring covered 
externally by a secretion of bone, | owing to the growth of the latter; 

* Todd and Bowman, p. 123. 

f Mem. de l'Acad. Roy. des Sciences, an. 1739-41-43-46. 
£ If a string be tied around a growing tree, the same thing takes place, and 
it is finally shut up in the ligneous part. 



106 SKELETON. 

and the medullary canal as large as the ring itself. Notwithstanding 
the obvious conclusion from this experiment, he made the mistake 
of supposing that the bone had enlarged by expansion, and not by 
a deposite externally with an absorption internally. 

As the individual advances in life, the cylindrical canal, in the 
centre of the long bones, continues to enlarge in size by the internal 
absorption : so that the parietes of the bones, which in early life were 
much thicker than the canal, and in the adult about the same dia- 
meter, become exceedingly thin in old age ; resembling thereby a 
stalk of Indian corn, with the pith scooped out.* The cells of the 
cellular structure in the several bones also enlarge, whereby the 
whole weight of the bones is much decreased in the very aged. In 
the parietes of the cranium there is rather a tendency to the absorp- 
tion of the diploe, and the approximation of their tables in extreme 

old age. 

The bones, also, become more brittle in old age, in consequence 
of the increase of calcarious with a diminution of gelatinous matter. 
The reverse being the case in infancy, they are more flexible than 
in the adult, and can even bear to be twisted or bent without break- 
ing, f 

* There are several examples of this in the Anatomical Museum. More 
rarely the reverse takes place, and the cavity is filled up : of this there are also 
specimens. 

f The reported instances are now numerous, where, from a defective organ- 
ization of bone, fracture is produced from very trivial causes; and this state is 
not confined to any particular age, for it extends from infancy to advanced life. 
I have attended a fractured os femoris in a child of two years, from a stumble 
in walking across a carpeted floor. In another child the os femoris was broken, 
so far as could be learned, by the nurse stooping- to reach something from the 
floor: the same child had both clavicles broken, without any one knowing 
when or where: the left side was flattened, from the fracture, probably a par- 
tial one, of several ribs, equally inexplicable. In a third child the tibia was 
broken from a trifling fall on the floor, and the clavicle from striking the 
shoulder moderately against the rounded back of a chair. 

In these several instances the fragility may arise either from an abnormal 
relation of the constituents of the bone to each other, by a deficiency of animal 
matter, which diminishes the tenacity of the bone, or it may arise from attenu- 
ation merely of the bone, leaving its parietes too thin for ordinary accidents. 



FORMATION OF CALLUS. 107 



SECT. III. — ON THE FORMATION OF CALLUS. 

As this is a consequence of bones being fractured, and a mode 
that nature takes to repair the accident, there is some resemblance 
between it and the primitive formation of bone. Owing to the 
rupture of the blood vessels of the bone ; of those of the periosteum, 
and of the medullary membrane ; and frequently of the vessels of 
contiguous parts, the first effect of the accident is an effusion of 
blood into the cavity of the fracture. The several contiguous soft 
parts then swell, become hardened and inflamed ; and, in the mean 
time, an absorption of the blood is proceeding, while an effusion of 
coagulating lymph from the ruptured vessels occurs in the cavity of 
the fracture. A ring, the thickest part of which is precisely over the 
seat of the fracture, is formed by the lacerated parts ossifying : there 
is also formed in the interior of the bone a sort of osseous pin. Till 
this moment the bone itself remains unchanged, with the exception 
of a coating of coagulating lymph on its broken faces ; but now its 
extremities begin to coalesce or fuse themselves into each other ; the 
superfluous bony matter (the ring and the pin) being no longer 
necessary, is absorbed, and the cavity of the bone with the mem- 
branes of the latter is re-established. In this case it will be seen 
that the deposite of coagulating lymph into the cavity of the fracture, 
corresponds Avith the mucous rudiments of the fetal bone, and that 
the remaining phenomena of ossification are the same. 

Some physiologists have attempted to give to the periosteum the 
exclusive credit of the formation of callus : the view is erroneous, 
because experiments show, that even where the periosteum is stripped 
designedly from the fractured ends of bones, they, nevertheless, 
unite, and the periosteum is restored when the callus is formed. 
The probability then is, that all the blood vessels (from whatever 
source they come) which penetrate the organized coagulating lymph 
secreted between the fractured extremities, convey and deposite 
calcarious matter. 

The celebrated Bichat and some others, were of opinion, that in 
every case of fracture where the ends of the bones are not kept in 
contact, granulations spring up from the ruptured surfaces of the 
bone, and of its membranes ; that these granulations first receive 
into their interstices a soft gelatinous deposite, then a cartilaginous 



108 SKELETON. 

one, and, finally, a calcarious one, by which the bone is united. 
This process, however, is much more common in compound frac- 
tures which suppurate, and may be considered rare in simple ones.* 

When the calcarious matter begins to take place in a forming callus, 
if the part be much moved, the process is arrested, the blood vessels 
no longer deposite even if they carry calcarious materials, and an 
artificial joint is formed. The proper period of restoration being 
once passed, the vessels sink into an inactive state from which they 
have little or no disposition to rouse themselves. Under these cir- 
cumstances, the late Dr. Physick proposed, many years ago, the in- 
troduction of a seton through the cavity of the fracture, and the re- 
taining of it there for a long time, for the purpose of stimulating the 
vessels. The plan has now been repeatedly tried, with success, upon 
the cylindrical bones, and, in one instance, upon the lower jaw.f 

Callus being formed much more speedily in young persons than 
in old, occasionally, however, we meet with instances in which the 
rapidity of its deposite in the latter is remarkable. I, for example, 
treated, in 1826, a female of ninety, for a simple fracture of. the os 
humeri, which was cured at the end of five weeks. 

* For a good account of the reproduction of bone, see Muller's Physiology 
by Baly, p. 455, &c ; where there is an analysis of the researches of Miescher, 
and several other authors. 

f Dorsey's Elements of Surgery. Philadelphia Med. and Phys. Jour. &c. 
There is now in the possession of Dr. J. Randolph, son-in-law of Dr. Physick, 
the os humeri upon which this experiment was first tried, and which shows, 
very satisfactorily, the state of union ; the hole is still left which the seton 
occupied. 



BOOK I. 

PART II. 

OF THE BONES, INDIVIDUALLY. 

The several textures of the body are so intermixed, that the con- 
sideration of one alone, pursued through all its applications, excludes 
for the time, rather artificially, some one or more of the others. This 
circumstance, inseparable from a clear account, has always perplexed 
"writers on anatomy, and left them under various impressions con- 
cerning the best point of departure and method for pursuing their 
descriptions. Reasons of value may be urged for almost any ar- 
rangement : each one will have some peculiar advantages that the 
others have not, and which will cause it to appear to the understand- 
ings of its advocates, superior to the rest. For a course of study 
which is intended to be physiological and surgical in its combina- 
tions, the usual practice of beginning with the skeleton is, perhaps, 
the most advantageous ; the young student will, however, under- 
stand that if the skeleton have any natural claim to this precedence, 
it is principally from its furnishing those land-marks, as it were, to 
which we refer the situation of other parts, and that it is only con- 
ceded, for the purpose of laying a foundation for their more easy 
and intelligible description subsequently. The human frame may 
be compared to an extended landscape, the multiplicity of whose 
features and the variety of objects spread over whose surface, col- 
lectively, bewilder the beholder; but by seizing first on its promi- 
nent outlines, marking the course of its mountains and ridges, and 
determining the bearings of the several objects according to them, 
we become able, at length, to define not only to ourselves, but to 
others, the precise position of each point, or each object which may 
be the subject of inspection. 

Unfortunately, the minuteness with which the skeleton is described, 
has been decried as useless, but the zealous and reasonable student 
Vol. L— 10 



110 SKELETON. 

ought to bear in mind — that the only rational plan of reducing a 
dislocated joint must depend upon a proper knowledge of its articu- 
lar faces ; that many of the great phenomena of life depend essen- 
tially upon the arrangement of the skeleton ; that locomotion is inse- 
parably connected with it ; and that, in short, it has a bearing upon 
almost every animal operation. With these facts impressed upon 
him, he will be prepared to give the description of the skeleton a full 
and perfect attention. 



CHAPTER I. 

The Trunk. 

The trunk is constituted by the Spine, the Thorax, and the Pel- 
vis. 

SECT. I. THE SPINE.* 

The Spine, (Columna Vertebralis, Rachis,) is placed at the poste- 
rior part of the trunk, and extends from the head to the inferior 
opening of the pelvis. It consists of twenty eight or nine distinct 
pieces, of which the upper twenty-four are true, or moveable verte- 
brae. The twenty-fifth is the sacrum, or the pelvic vertebra, which 
is fixed ; and the remaining three or four pieces are the caudal ver- 
tebrae or the coccyx. The sacrum and coccyx are false vertebra?, 
being so called from not turning. 

There are seven vertebrae to the neck, called cervical; twelve to 
the thorax, called dorsal ; and five to the loins, called lumbar. In 
reckoning the number of the vertebrae, the one next to the occiput is 
always the first; and so on, successively, to the last. Albinus, how- 
ever, has departed from this rule, and counts them from below, up- 
wards. 

On the posterior face of the spine, each of the true vertebrae is 
seen to contribute, by a long process, to that ridge which is so rea- 
dily felt beneath the skin, and from which, probably, the name of 
spine w T as derived. The spine increases gradually in size from the first 

* Anat. Atlas, fig. 15. 



THE SPINE. HI 

to the last true vertebra. The upper part of the sacrum is extended 
laterally much beyond the latter, afterwards the spine diminishes ab- 
ruptly to the extremity of the coccyx. The spine has several curva- 
tures, which are best marked in the erect position. For example, 
the lower part of the cervical portion is convex anteriorly, and con- 
cave behind — the thoracic part is concave in front, and convex 
behind — the lumbar portion is convex in front, and concave behind 
— the pelvic and caudal portion is concave in front, and convex be- 
hind. This arrangement is the result of the different degrees of 
thickness in the bodies of the vertebras, and especially in the fibro- 
cartilages which unite them to each other. Wherever these carti- 
lages are thin at their anterior margin, there is a concavity ; but where 
they are thick at the same point, there is a convexity. 

General Characters of a Vertebra. 

A vertebra (vertebre) consists in a body, in seven processes or 
extremities, and in a canal or foramen for lodging the spinal mar- 
row. 

The body of a vertebra is at its fore part; it is somewhat cylin- 
droid or oval, but varies considerably from these figures according 
to its position in the spine. The anterior part of the body is con- 
vex ; but the posterior part is concave, where it contributes to the 
spinal canal. The superior and inferior surfaces are flat, with the 
exception of a ridge of hard bone at the circumference, more ele- 
vated, and not so extended in some bones as in others. These 
ridges are, in young subjects, epiphyses. There are many foramina, 
large and small, to be seen on the front and back surfaces of the 
bodies. They transmit arteries and veins, and some of them are 
used for fastening the ligaments of the spine. On the posterior face 
of the body there are two foramina larger than the others, occupied 
by veins coming from the interior of the vertebra. These veins 
correspond with the diploic sinuses in the head, and have been par- 
ticularly described by M. Breschet, of Paris, in a thesis presented to 
the School of Medicine in 1819. 

The processes are placed at the posterior part of a vertebra. 
Of these there are four oblique or articulating processes, which 
articulate with the corresponding ones of the bones, above and be- 



U2 SKELETON. 

low ; two transverse processes, which project, one on either side, 
from between the oblique processes ; and one spinous process, 
which is placed on the middle of the bone behind. The two ob- 
lique, and the transverse process on each side, come from a com- 
mon base or root that arises from the lateral posterior part of the 
body, and present collectively a very irrregular appearance. Their 
faces and inclinations are much modified in the several vertebrae. 
The spinous process is also much modified in regard to size, shape, 
and inclination. 

The body and processes form the periphery of the foramen for 
the spinal marrow, and, by their thickness and strength, afford an 
excellent protection to the latter. This spinal foramen is of a tri- 
angular prismatic, or of a rounded cylindrical shape, presenting its 
base in front and its apex behind. It is considerably larger than the 
spinal marrow of the part, including its vessels, membranes, and the 
nerves that proceed from it ; in this respect the foramen differs very 
materially from the cavity of the cranium, which is exactly filled by 
the brain. 

At the upper part of the spinal foramen of a vertebra, between the 
body and the upper articulating, or oblique process, is a groove. 
There is another groove between the lower oblique process and the 
body. These grooves, by the approximation of the contiguous ver- 
tebra?, are converted into perfect holes, called inter-vertebral fora- 
mina, and are for the transmission of the spinal nerves and blood- 
vessels. 

The bodies of the vertebrae are extremely light and spongy, be- 
ing formed principally of the cellular matter of bone, and are 
covered, with a very thin lamella of compact substance, with the 
exception of their upper and lower surfaces, where this covering is 
thick at the circumference owing to the epiphyses. The processes, 
for the most part, have a thick and compact structure, enabling them 
to sustain conveniently the weight of the body and the action of the 
different mus les, as applied to them. 



c 



Of the Cervical Vertebrae. 

Common Characters. The cervical vertebrae differ among them- 
selves, but are easily distinguished from the other bones, of the 



THE SPINE. 113 

spine. Their bodies and processes are small, but the spinal fora- 
men is large, so as to admit of much motion, -without pressing on 
the spinal marrow. The fore and back parts of the body are more 
flattened. The upper face is concave transversely, being bounded 
on each side by a ridge of bone ; the lower face is concave from be- 
fore backwards, and is bounded by a ridge before and behind. This 
arrangement permits the bodies of adjoining vertebrae to embrace 
each other in the dried bones, and grants great facility of motion, in 
the living body, by the interposition of a thick inter-vertebral sub^ 
stance ; as well as security in the attachment of the latter. 

The oblique processes have their articular faces at an angle of 
about forty-five degrees. The superior face upwards and backwards, 
the inferior downwards and forwards. The spinous process is short, 
triangular, nearly horizontal, and bifurcated at its posterior extremity, 
where it terminates in two tubercles. The transverse processes are 
short, and perforated by a large canal for ;he transmission of the 
vertebral artery and vein ; they are concave above, somewhat convex 
below, and present two points at their external extremities for the 
origin and insertion of muscles. The inter-vertebral foramen is 
formed principally by the lower of the two contiguous vertebrae, but 
the difference in the contribution of the two is inconsiderable, and is 
liable to variations in different skeletons, and indeed on the bones 
of the same set. 



Of the Cervical Vertebrce, individually.* 

The first cervical vertebra, commonly called the Atlas, from its 
supporting the head, presents the appearance of a large irregular 
ring, much thicker at its sides than elsewhere. It is deficient in 
body, owing to the space allotted to that part in the other vertebrae 
being occupied by the processus dentatus of the second vertebra. 
The place of body is supplied by an arch of bone. 

Its oblique processes are peculiar, both in shape and position. 
The upper ones are concave and horizontal, their long diameters 
being extended from within outwards and backwards, so as to suit 
the direction of the condyles of the occipital bone with which they 
articulate ; the greatest depth of their concavity is, therefore, internal. 
The inferior oblique processes are smaller, slightly concave, and 

* Anat. Atlas, Figs. 19, 20, 21, 22. 
10* 



114 SKELETON. 

circular; they rest upon the shoulders of the second vertebra. At 
the internal margin of the oblique processes a rounded tubercle is 
found on either side of the bone. The transverse ligament of the 
neck is extended between the two tubercles, and keeps the processus 
dentatus in its plaee. 

The short thin bridge at the fore part of the bone, is marked in 
front by a tubercle, and behind by an articular face which touches 
the processus dentatus. The bridge or section of the ring forming 
the posterior part of the bone, is much longer and more arched than 
the anterior. It also has in its centre a tubercle, occupying the posi- 
tion of a spinous process. At the anterior extremity of this bridge, 
just behind the upper oblique process, there is a groove, and some- 
times a canal, made by the vertebral vessels, just before they enter 
the foramen magnum occipitis. 

The transverse processes of this vertebra are at the sides of the 
thick part of the ring. From their greater length, they project con- 
siderably beyond the transverse processes below, and are also per- 
forated at their bases by the vertebral vessels, which have a very 
winding course from them into the cranium. 

The spinal canal of the first vertebra, excluding the space for the 
processus dentatus and transverse ligament, is the largest in the 
spine: by which ample provision is made against injuries of the 
medulla spinalis, notwithstanding the great latitude of the rotation of 
this bone upon the second vertebra. A considerable vacuity is left 
between the upper posterior margin of the atlas and the contiguous 
surface of the os occipitis, for the ginglymoid motion of the head upon 
the atlas. 

The second vertebra of the neck is particularly remarkable for the 
elongation of its body above into the processus dentatus or tooth-like 
process. This process rises as high as the superior margin of the 
atlas, and almost touches the anterior margin of the foramen mag- 
num occipitis.* It presents an articular face in front, where it 
touches the first vertebra. It presents also a smooth face behind, 
where it touches the transverse ligament. Above the latter face, 
&n. each side, is a flat surface for the origin of the moderator 
ligament, and the very point above presents a small rough surface 
for the vertical ligament going to the margin of the foramen 
magnum. 

* Sometimes it even forms a joint with it.. 



THE SPINE. 115 

On each side of the tooth-like process, this bone presents its 
superior oblique process, as a shoulder, nearly horizontal, circular, 
and somewhat convex. The inferior oblique process has nothing 
peculiar either in its position or direction. The foramen of the trans- 
verse process is directed upwards and outwards. The interior part 
of the body, like that of the other vertebrae, is cellular. 

The posterior part of the second vertebra is strong and broad. 
The spinous process is longer than any other except the seventh, 
and sometimes the sixth ; it is also much larger, is triangular, presents 
a ridge above and a fossa below, and is bifurcated at its extremity. 
Just behind the upper oblique process there is a very superficial 
notch, scarcely discernible, for the inter-vertebral foramen. The 
processus dentatus is the pivot or axle upon which the head revolves, 
and is stationary while such motions are going on. The spinal canal 
of this vertebra is cordiform or circular instead of triangular. 

The vertebrae of the neck increase gradually in the size of their 
bodies from the second to the seventh ; and there is sufficient uni- 
formity between them, with the exception of the last, to render the 
general description applicable, though it is not difficult to observe 
some minute and unimportant points of difference. 

The spinous process of the sixth vertebra is long, and terminates 
in a sharp point. 

The seventh cervical looks like a dorsal vertebra, and has some 
peculiarities which are well marked. Its body is larger, its superior 
face is less concave than in the others, and its inferior face is flat. 
Its spinous process is the longest of all, is not bifurcated, but termi- 
nates by a rounded tubercle easily felt beneath the skin. Its trans- 
verse processes are thrown somewhat backwards, and though there 
is a small foramen in them, it is not large enough to receive the ver- 
tebral vessels. Sometimes on the side of its body, at the lower 
margin, is a small face, by which it partially articulates with the head 
of the first rib. 

M. Portal* reports, that in some rare cases he has seen only six, 
and in others, eight cervical vertebras ; either of which deviations I 
have never met with. 

* Anat. Medicale. Paris, 1803. 



116 SKELETON. 



Of the Dorsal Vertebra* 

General or Common Characters. — The dorsal vertebrse, amounting 
to twelve, being intermediate in position to those of the neck and 
loins, are also intermediate in size. They diminish in the transverse 
diameter of their bodies from the first to the third : afterwards, they 
increase regularly in size to the last. 

Their bodies are more cylindroid than those of the neck, and the 
most of them are marked laterally on the upper, and also on the 
lower margins, near the base of the processes, with a small articular 
face, which receives one-half of the head of a rib. The adjoining 
fossa of the contiguous vertebra, receives the other half of the head 
of the same rib. The superior of these articular faces is larger than 
the inferior. The superior oblique processes are fiat, and present 
almost backwards ; the inferior are also flat and present as directly 
forwards. The transverse processes are directed obliquely back- 
wards: they are long, terminate in an enlarged extremity, which 
presents an articular face in front for the tubercle of the contiguous 
rib. The transverse processes as they descend are directed more 
backwards, and diminish in length. . The spinous processes are long, 
triangular, with a broad base, and an extremity somewhat rough, 
swollen, and sharp-pointed, except in the upper and lower vertebra? : 
they have a ridge above and a fossa below; are directed obliquely 
downwards, and overlap each other. 

The spinal foramen is small and round. The notch for the inter- 
vertebral foramen is formed principally by the upper of the two con- 
tiguous vertebrse above. 



Of the Dorsal Vertebra — individually. 

These vertebra?, though they have many common points of re- 
semblance, yet some of them present distinguishing peculiarities. 
Of these, the first and the two or three last, are the most re- 
markable. 

The first has a complete articular face on the side of its body for 
the head of the first rib, and a partial surface at its lower margin for 
the head of the second rib. Its spinous process is projecting and 

* Anat. Atlas, Figs. 23, 24. 



THE SPINE. 117 

not so oblique as some of the others : the flatness of its body makes 
it look much like a cervical vertebra. 

The three lower dorsal vertebrae approach in the form of their 
bodies to those of the loins. Frequently, but not always, the tenth 
has the articular face for the head of the rib, equi-distant from its 
upper and lower margins, and its transverse process so short, and 
inclined backwards, that the tubercle of the tenth rib does not form 
an articulation with it. The eleventh and twelfth vertebra? have also 
the fossae for the heads of the ribs, in their middle, at the sides of 
the roots of the processes; instead of a partial pit at their upper and 
lower margins. Their transverse processes are remarkably short, 
are directed almost backwards, and do not touch the ribs, and have, 
therefore, no articular marks. The spinous process departs from the 
triangular shape, becomes flattened and vertical at its sides, is not 
far from being horizontal, and has a tubercle at its extremity. 

The middle vertebrae of the back have some minute points of dif- 
ference among themselves, the most of which it would be useless to 
study. They increase, as stated, gradually in size as they descend, 
and their spinous processes are very near to, and overlap each other, 
like shinnies on the roof of a house. 



Of the Lumbar Vertebra* 

Common Characters. — Their number has been stated at five. 
Their bodies are larger than those of the other true vertebras, and 
are oval on the upper and lower surfaces, with the long diameter 
transverse. The epiphyses at the margins of these faces, are larger 
and more elevated. The spinal foramen is triangular and more 
capacious than in the dorsal vertebras. The inter-vertebral notches 
for the nerves to pass out, are much larger than elsewhere in the 
spine, and are formed principally by the upper of the two contiguous 
vertebrae. 

The transverse processes are very long, and stand out at right 
angles. The articular faces of the upper oblique processes are con- 
cave and vertical, being directed very much inwards, or looking 
towards each other; the lower oblique processes are convex, and 
have the articular faces directed very much outwardly. The spinous 

* Anat. Atlas, Figs. 25, 26, 27. 



118 



SKELETON. 



process is short, thick, and horizontal ; having broad, flat sides, and 
terminating by an oblong tubercle. 

Of the Lumbar Vertebra, individually. 

These bones are not so well marked among themselves as the 
other vertebrae. They may be distinguished in a single set, by the 
successive increase in the size of their bodies. The first, therefore, 
is known by its being the smaller ; by the comparative shortness of 
its transverse process, and by the deep concavity between the supe- 
rior oblique processes. 

The transverse and spinous processes of the three middle vertebra? 
are rather longer than those of the others ; the third has them the 
longest of all. The last lumbar vertebra may be recognised by its 
greater size ; by its body being flat, and thicker in front than behind, so 
as to give it somewhat of a wedge shape ; by the greater size of its 
spinal foramen ; by the obliquity backwards of the transverse process ; 
and by the wide interval between the oblique processes, as well as 
by the lower of the latter facing almost directly forwards. 

Of the Pelvic Vertebrce* 

The os sacrum, [sacrum,,') the largest hy much of any of the bones 
in the spinal column, has obtained its name from the supposition of 
its having been offered in sacrifice by the ancients, f It forms the 
posterior and superior boundary of the pelvis, as well as the pedestal 
of the spine, and may, therefore, be properly studied along with 
either of them, though its association with the spine seems more 
natural. In its lateral boundaries it is triangular: it is also regularly 
concave before, and very irregularly convex behind. 

In its forming state this bone consists of five pieces, separated by 
long narrow interstices filled with cartilage. It is in this condition 
that its pieces bear a very strong resemblance to the true vertebrae, 
and, therefore, have obtained the name of false vertebrae. They are 
all fused into one by the progress and development of the bone ; but 
the marks of the original separation remain, particularly on its front 
surface. 

* Anat. Atlas, Figs. 28, 29. f Portal. Anat. Med. vol. i. 345. 



THE SPINE. 119 

Though the anterior face of the sacrum presents generally a regular 
concavity ; in some subjects, nevertheless, it is flat. This surface is 
pierced on each side by four holes, which communicate with the 
spinal cavity and transmit the anterior nerves of the cauda equina. 
Beneath each range of holes is a notch, which by the corresponding 
one of the coccyx, is converted occasionally into a perfect foramen 
for the thirtieth spinal nerve, or for the fifth of the sacrum. These 
foramina diminish in size, from the higher to the lower : their orifices 
are funnel-shaped, and directed obliquely outwards. Horizontal 
ridges of bone, marking the original separation of the false vertebrae, 
connect the holes of the two sides. 

The false vertebras decrease in size from above, which is mani- 
fested by the successive approach of the foramina, and of the hori- 
zontal ridges. The first of them has almost the same vertical dia- 
meter as the last of the loins, and sometimes a greater one, especially 
in the male subject ; besides its great increase of magnitude by the 
lateral extension of its base. 

The posterior face of the sacrum is very convex and rough, and 
is equally divided by its spinous processes. The processes belong- 
ing to its three upper sections or bones, are for the most part well 
marked, and decrease in length from the first. The fourth spinous 
process is resolved into two tubercles, and the fifth is fairly sepa- 
rated also into two tubercles, by an angular fissure, with its base 
downwards and open. This fissure, it may be remarked, sometimes 
invades the fourth spinous process, and even the third, and in some 
rare cases runs the whole length of the posterior surface of the bone, 
leaving a gap from one end to the other. The upper margin of the 
posterior face of the sacrum presents on each side an oblique process 
for articulating with the lower oblique processes of the last lumbar 
vertebra. Just above the upper spinous process is a deep notch, 
between which, and the last lumbar vertebra, is a very large vacuity, 
or gap, exposing the spinal canal. 

On each side of the spinous processes are also four foramina, 
smaller and thinner than those in front, and for the passing of the 
posterior nervous cords from the cauda equina. At their internal 
margins some small and obscure risings of bone are perceptible, 
which may be considered the rudiments of oblique processes. On 
the outer side of these foramina, there are several more strongly 
marked tubercles, from which the sacro-iliac ligaments arise. Be- 
yond these the posterior surface of the bone slants very considerably 



120 SKELETON. 



to its lateral margin ; the entire surface of this slant, and which is 
irregularly pitted, being devoted to the origin of ligamentous matter 
connecting it with the ilium. 

The base of the sacrum presents in its middle an oval surface for 
articulating with the body of the last lumbar vertebra. Between this 
surface and the oblique process, may be remarked the groove for the 
fifth lumbar nerve. The base of the sacrum continually thickens, 
from the side of the oval surface to the place of junction with the 
ilium. The anterior margin of this expansion is continuous with 
the linea ilio-pectinea ; the posterior margin is elevated at its ex- 
tremity, is a substitute for a transverse process, and is placed im- 
mediately below the transverse process of the last lumbar vertebra. 
The point of the sacrum is truncated where it articulates with the os 

coccygis. 

The lateral face of the sacrum is thicker above than below ; its 
upper two-thirds present an irregular, and somewhat triangular ar- 
ticular face for joining the ilium ; the lower third is very thin, and 
contributes to form the sacro-sciatic notch of the pelvis. 

The spinal canal of the sacrum is triangular, and diminishes con- 
tinually to its lower extremity, where it terminates by a small orifice, 
notched behind, as mentioned, and exposing the last piece of the 
bone. The foramina on the anterior and posterior surface of the 
sacrum, communicating with thjs canal, correspond strictly in their 
uses and positions with the inter-vertebral foramina of other parts of 
the spine. 

The sacrum is extremely light for its size, and its texture is in a 
hio-h degree spongy ; but its processes and articular faces are quite 
as compact as they are in other parts of the spine. 



Of the Coccyx or Caudal Vertebra* 

The os coccygis (coccyx) resembles the sacrum in shape and tex- 
ture, and is so placed as to continue forwards the line of the curva- 
ture of the sacrum. It consists in four small pieces, sometimes only 
three, united to one another by fibro-cartilaginous matter, and it 
corresponds with the tails of animals. These pieces in the progress 
of life, are not only anchylosed together, but also with the sacrum ; 

* Anat. Atlas, Fig. 30. 



THE SPINE. 121 

so that all the false vertebrae, from the base of the sacrum to the point 
of the. coccyx, are joined into a single bone. 

The upper bone of the coccyx is the largest, and is the base of 
this little pyramidal pile ; it is united, by its middle, to the truncated 
apex of the sacrum ; and its sides, moreover, are, in the perfect 
specimen, elongated several lines beyond this surface of contact. 
From the posterior surface of the first bone, of the perfect coccyx, a 
tubercle arises on either side, which is curved upwards, and joins the 
bifurcated termination of the last spinous process of the sacrum: 
between the two bones an inter-vertebral foramen is thus left for the 
passage of the fifth sacral nerve from the canal of the sacrum. 
Immediately below this tubercle is a notch, made by the sixth sacral 
nerve. 

The remaining bones of the coccyx are much smaller than the 
first, and diminish successively. The surfaces which they all present 
to each other are somewhat concave in the centre. The lower end 
of the last bone terminates in a rough point, to which a cartilage is 
appended. These bones are very spongy and light : their principal 
strengdi is derived from a ligamentous covering. To them are 
attached the sacro-sciatic ligaments, the coccygsei, levatores ani, and 
the glutaei magni muscles. 



SECT. II. DEVELOPMENT OF THE VERTEBRAL COLUMN. 

This column is much longer, in proportion to the limbs, at birth, 
than it is in adult life, and upon it depends the principal length of 
the individual at this period. The head is always in proportion to 
the length of the spine. This predominance in the head and spine 
is, no doubt, connected with the necessity of an early development 
in the nervous, respiratory, and alimentary systems, in order to 
maintain the life of the individual ; whereas, the use of the upper and 
lower extremities being called for only at a more advanced period, 
their development is not in proportion. It is remarked, that in adult 
life the principal difference in the stature of individuals depends 
upon the length of the lower extremities ; the trunk, including the 
head, being of nearly the same length in all. This rule, however, 
like most others, has numerous exceptions. The spinal canal and 
the inter- vertebral foramina are, also, proportionably larger in the 
foetus. 

Vol. L— 11 



122 SKELETON. 

The spine of the foetus is but badly suited to the purposes of 
standing and walking. Its spinous processes are deficient, in con- 
sequence of which, the muscles which are intended to keep it erect, 
have their insertion so much in the line of motion, that they perform 
their part very imperfectly, and the spine is continually bending 
forwards, from the erect position. All the transverse processes are 
also imperfectly developed, those of the loins are particularly defi- 
cient; those of the thorax and neck are less deficient, as in the one 
case they have to form an articular surface for the ribs, and in the 
other to allow passage to the vertebral artery. The bodies of the 
vertebrae are imperfectly ossified, and are separated by cartilage 
from the processes. The epiphyses, or upper and lower surfaces 
of the bodies, are in the state of cartilage : the bodies, therefore, 
are rounded both above and below, whereby their surfaces of contact 
are much reduced in extent, and the line of support to the trunk 
rendered much less firm. When, at this age, the vertebrae are 
macerated, their bodies present themselves as small rounded tuber- 
cles; and very nearly one-half the whole length of the spine is made 
up of the cartilaginous epiphyses and the inter-vertebral cartilages. 
The spine, in the foetus, is almost straight, and scarcely presents at 
all those curvatures, for which it is so remarkable in adult life. This 
depends upon the rounded form of the bodies of the vertebrae, and 
the sameness of thickness in the inter- vertebral matter at its anterior 
and posterior edge. 



SECT. III. ON THE USES OF THE VERTEBRAL COLUMN. 

The vertebral column performs three important offices in the animal 
economy. It affords a secure lodgement to the spinal marrow ; is- 
a line of support to the trunk, in every variety of position ; and is the 
centre of all its movements. 

In standing, the spine also supports the head, which it can do very 
conveniently, from the horizontal direction of the condyles and their 
nearly central position on the occiput, and from the head being 
almost in equilibrium when we stand erect. The volume of the 
head is so much greater before the condyles than behind them, that 
upon a superficial view one would suppose its preponderance in front 
to be very considerable. This is, however, less than it might seem 
to be, for two reasons : one is, that the diameters of the head are 



VERTEBRAL COLUMN. 123 

augmented behind the condyles, and, secondly, it is formed of solid 
matter there ; whereas, in front a great deal of it is hollow, for the 
construction of the nose and the sinuses bordering upon it. The 
head, though nearly balanced then, has some preponderance in 
front, which is manifested by its falling forwards whenever we sleep 
in the erect position, or when the sudden suspension of life destroys 
the contraction of the muscles on the back of the neck. 

In the lower orders of animals, the obliquity of the condyles, their 
situation at one end of the head and the great length of the face, 
acting as a weight upon a long lever, have a continual tendency to 
incline the head downwards ; which is only partially counteracted 
by the largeness of the muscles and ligaments on the back of the 
neck. 

The horizontal direction of the condyles, and their location near 
the centre of the base of the head, have arrested the attention of 
naturalists, and established for man characters distinguishing him, 
from all other animals, for facility in maintaining the erect attitude. 
Bichat happily observes, that from this conformation result the fol- 
lowing peculiarities in his organization: 1. Less strength in the 
muscles of the neck than in quadrupeds; 2. Less projection in the 
occipital bone, where the muscles are inserted; and, 3. An imper- 
fect development of the ligamentum nuchas. 

The thoracic and abdominal viscera, by being placed in front of 
the spine, and without a counterpoise behind, have a continued 
tendency to bend it. This is only resisted by the muscles which fill 
up the long gutter on either side of the spinous processes, and are 
inserted into the ribs, the spinous and the transverse processes. The 
lumbar vertebras and the appertaining muscles and ligaments, having 
an increased duty to perform, from the lowness of their position, and 
the variety of their movements, become the soonest affec'ed by fatigue 
and bodily weakness ; and therefore manifest sooner the sensation of 
lassitude, notwithstanding the augmented volume of the bodies and 
processes of these vertebras, and of the muscular masses inserted into 
them. 

The mechanical arrangement of the spine permits it to perform 
the motions of flexion, extension, lateral bending, circumduction, 
and rotation. 

1 . Flexion, or that posture in which the spine is bent forwards, is 
the most extensive of its movements : the general mechanism of the 



124 SKELETON. 

human body disposes us to approach surrounding objects in that 
direction ; and the muscles of the abdomen, besides their intrinsic 
strength, act most advantageously in producing it, by being removed 
to a great distance from the centre or line of motion. In this posi- 
tion the inter-vertebral cartilages are diminished or compressed in 
front, and thickened behind, the anterior vertebral ligament is in a 
state of relaxation, while the posterior vertebral ligament, the elastic, 
and those which connect the spinous processes, are in a state of pro- 
portionate tension. 

2. The motion of extension, on the contrary, is much more limited 
from several causes. The muscles which act in this case, by arising 
either from the posterior face of the pelvis, or from the transverse 
processes, and going upwards to be inserted either into the ribs, the 
transverse or the spinous processes, are much less advantageously 
placed than the abdominal muscles, in regard to the length of the 
lever which they employ. Moreover, mechanical obstruction is op- 
posed to this motion by the spinous processes of the back and neck, 
being very near to, and overlapping each other. The abdominal 
muscles also afford a strong resistance to its being carried beyond a 
certain point as any one may assure himself of, by the tension com- 
municated to these muscles from placing a large billet of wood under 
the loins of a subject; and, when they are cut through transversely, 
the immediate consequence is, a great increase in the posterior flexion 
of the spine, through the agency of the lower dorsal and the lumbar 
vertebrae. The anterior vertebral and the inter-vertebral ligaments, 
likewise, oppose the extension of the spine, much more than the 
elastic and the inter-spinous ligaments do its flexion. 

3. The lateral inclination of the spine is a motion of considerable 
extent, and is obtained both by the very advantageous position of 
the muscles on the side of the trunk and neck, and by the little 
mechanical resistance to it from the shape and arrangement of the 
parts concerned. A principal impediment to this motion being car- 
ried beyond a certain point, is presented by the ribs striking against 
each other. The transverse processes of all the vertebrse are so far 
apart, particularly in the loins, that they scarcely deserve to enter 
into the estimate of resistances. As the muscles of the one side 
produce the lateral curvature, so their resistance on the other limit it 
to a certain extent, as may be readily ascertained by cutting them 
through. 



vertebral column. 1-25 

4. The circumduction of the spine is that motion in which the 
trunk is caused to describe a cone, the base of which is above, and 
the apex below. It is performed on the lower dorsal and the 
lumbar vertebrae, and is a succession of the movements already 
described. 

5. The rotation of the spine is a very limited motion. It is per- 
formed almost entirely on the lower dorsal and the upper lumbar 
vertebrae, and presents in its analysis a series of minute and oblique 
slidings of the bodies of the vertebrae upon one another, the pivots 
being the oblique processes. The action occurs by the lateral yield- 
ing of the inter-vertebral substance ; it must, therefore, be almost in- 
conceivably small in any individual substance, particularly when the 
latter has been hardened and rendered more fibrous by old age. In 
the very young subject it is more appreciable. 



Of the Motions peculiar to each Class of Vertebra. 

1. The cervical vertebrae, as a whole enjoy a considerable share 
of flexion, extension, lateral inclination : and of circumduction, as 
the result of the other motions. Their rotation, or the oblique 
sliding of one vertebra upon the other, is very limited. The appa- 
rent facility with which they are twisted upon each other, when the 
face is turned to the shoulders alternately, is almost wholly the mo- 
tion of the first vertebra upon the second, the participation of the 
other vertebrae being very inconsiderable. The possibility of the 
dislocation of these vertebrae, with the exception of the first, is very 
stoutly denied by authorities of the first standing in anatomy, on the 
score that too great a resistance to this accident is afforded by the 
inter-spinal and inter-transverse muscles, by the inter-locking of the 
bodies of the vertebrae through their reciprocal concavities and con- 
vexities, and by the shape and extent of their oblique processes. 

Many years ago, I met with a case in which there was every 
reason to believe that a partial displacement or dislocation had oc- 
curred about the fourth vertebra, in a boy of eight or ten years. It 
arose from his struggling to extricate himself from the grasp of a 
school-mate, who held him near the ground by the back of the head, 
with the spine bent forwards. This position, it is evident, w T as cal- 
culated to lift the oblique processes of the vertebrae above over the 

11* 



126 SKELETON. 

others ; and an oblique force applied at the same time consummated 
the accident, by twirling the lower oblique process over the upper 
margin, and in front of the one with which it was articulated below. 
The displacement was manifested by inability to move the neck ; 
by a permanent inclination and turn of the head to the side opposed 
to the injured one ; and by an inequality in the range of the anterior 
points of the transverse processes of the side affected. I succeeded 
in replacing the bone by lifting its dislocated side over the oblique 
process of the vertebra below, communicating at the same moment 
a rotatory motion, the reverse of that by which the accident had 
happened. In an instant, the patient was relieved ; from extreme 
pain, fixed deformity, and inability to move the neck, he performed 
with freedom all the motions natural to the part.* 

The principal motions of the head upon the first vertebra are those 
of flexion and extension ; the power of the condyles to slide horizon- 
tally from one side to the other in the cavities formed in the atlas, is 
narrowly restricted, both by the shape of the proximate articular sur- 
faces, and by the arrangement of the ligaments : this motion is, in fact, 
so inconsiderable as scarcely to deserve notice. Even flexion and ex- 
tension appear greater than they actually are, in consequence of the 
lower vertebra; most commonly concurring in these motions. When 
simply the head is flexed upon the atlas, while the other vertebrae 
are kept erect, the chin approaches the sternum, and the skin of the 
neck is thrown into folds ; but when all the bones are flexed, the 
head is thrown forwards and the skin is kept tense. The flexion of 
the head upon the atlas is restricted by the ligamentum nuchae, and 
by the ligament passing from the posterior margin of the occipital 
foramen to the posterior bridge of the atlas. The extension of the 
head is restricted by the vertical, moderator, and anterior vertebral 
ligaments. 

The motion of the atlas upon the axis is limited strictly to rota- 
tion. The confinement of the processus dentatus by the transverse 
ligament behind, and by the anterior bridge of the first vertebra in 
front, prevents thoroughly both flexion and extension. The hori- 
zontal direction and the flatness of the corresponding articular faces 
of these two vertebrae, also prevent any lateral inclination. In com- 
pensation for these restrictions, the rotatory motion is enjoyed to 

* I have lately seen another accident of the same kind from a fall. See 
Med. Examiner, 1842. 



VERTEBRAL COLUMN". 127 

great extent, and is amply provided for, by the extreme looseness 
and thinness of the capsular ligament of the oblique processes. In 
this motion the arch of the atlas and the transverse ligament rotate 
on the tooth-like process to the right and left alternately ; at the same 
time the inferior oblique process of the atlas is slid either forwards 
or backwards, according to the general movement upon the upper 
oblique process of the dentata. This movement is checked, at a 
certain point, by the moderator ligaments, which, by the close con- 
nexion of the head and first vertebra, answer the same purpose as if 
they were inserted into the latter. It is also checked by the capsular 
ligament, notwithstanding the general laxity of the latter. But still 
it is not difficult for it to exceed its natural bounds, and for the 
oblique process of the atlas to pass completely beyond the margin of 
that of the dentata, and in returning to lock against it. This, in 
fact, happens, in the great majority of instances, where violence 
from falls, and so on, has been applied to the body, and results in 
injury to the neck, particularly ; and when, in the abrupt turning of 
the head, produced by the action of the muscles, the individual finds 
himself incapable of bringing it back. This articulation is, unques- 
tionably, less protected, and more exposed to accident, than any 
other in the spine ; and, as just stated, is therefore supposed, by 
some, to be the only one in the neck admitting of simple luxa- 
tion. 

Most frequently, in this luxation, when it is produced by external 
violence, death is the immediate- result, from the spinal marrow 
being pressed upon and disorganized above the origin of the phrenic 
nerve. The seat of the principle of respiration is in the medulla ob- 
longata, and its agents are the phrenic and the intercostal nerves ; 
the communication with which being thus cut ofF, respiration, and 
consequently circulation, stop immediately. Bichat thinks, that 
when death is thus suddenly produced, the processus dentatus, by 
rupturing its own ligaments connecting it to the occiput, slides by 
the falling of the head forwards, beneath the transverse ligament, and 
presses upon the spinal marrow. On the contrary, when it is a 
simple displacement of the oblique processes, as the odontoid pro- 
cess remains within its boundaries, and its ligaments are only 
stretched, there is no danger of death. Fatal accidents have hap- 
pened to this articulation, in holding an infant from the ground, by 
the two hands applied to the head, from his struggles to disengage 
himself. A posture-maker is said to have died on the spot, from 



128 SKELETON. 

communicating a rotatory motion to his trunk, while its weight was 
sustained by inverting his head, and making the latter the base of 
support. When the vertebrae are displaced in such persons, as well 
as in those hung by the neck, it is supposed that the sliding of the 
processus dentatus from beneath the transverse ligament takes place ; 
as, by experiments on the dead body, it is found that such displace- 
ment occurs much more readily than the rupture of the transverse 
ligament. 

2. The dorsal vertebrae are capable of but very little motion in 
any direction. The rigidity and length of the sternum prevent them 
from flexion, the overlapping and obliquity of their spinous processes 
prevent them from extension, and the ribs prevent them from lateral 
inclination. It is, however, to be observed, that as those obstacles 
are diminished, succcessively, in the five lower dorsal vertebra?, con- 
sequently they become more and more capable of motion upon each 
other. Luxation among them, at any point is thought to be impos- 
sible, from the strength of their ligamentous attachments, and from 
the arrangement of their articular faces. 

3. The lumbar vertebra? move with great comparative freedom 
upon one another ; admitting, as stated, of flexion, extension, and 
lateral inclination. Below, however, they are much more restrained 
than they are above ; hence, it results, that the principal seat of the 
motions of the trunk upon the spine, is about the connexion of the 
lumbar and dorsal vertebra?. Dislocation is here, also, thought to 
be impossible, from the strength of their ligamentous attachments, 
from the great diameters of their bodies, and from the deep inter- 
locking of the oblique processes. 



SECT. IV. — OF THE OSSA INNOMINATA.* 

(Os Coxaux, ou des lies.) — These bones, two in number, are situ- 
ated one at either side of the sacrum, and constitute the lateral and 
anterior parietes of the pelvis ; forming, along with the sacrum and 
coccyx, the whole of this latter cavity. 

The os innominatum, from having been, in its original state, in 

* Anat. Atlas, Figs. 31, 32. 



OSSA INNOMINATA. 129 

three pieces, notwithstanding they subsequently coalesce firmly in 
the adult, and preserve scarcely any vestige of their primitive dis- 
tinction, is divided by anatomists into ilium, ischium, and pubes. 

Os Ilium, (Ilion.) — This, the largest of the three portions, forms 
all the upper rounded part of the os innominatum, and is the haunch 
bone of common language. Its superior margin is a semicircle, 
rather thicker towards the extremities than in the middle. The 
inequality, when viewed from above, is very apparent, as well as 
a slight curvature resembling the letter S. This margin of the 
bone is called its crest or spine, presents an internal lip for the 
origin of the transversalis abdominis muscle, an external one for 
the insertion of the obliquus externus, and an intermediate edge 
for the origin of the obliquus internus. The anterior extremity of 
the spine is terminated by a projecting point, called the anterior 
superior spinous process, from which arise the tensor vagina? femo- 
ris, the sartorius, and the beginning of Poupart's ligament. The 
posterior extremity of the crest is also projecting and pointed, but 
less so than the other, and obtains the appellation of the posterior 
superior spinous process. 

The anterior margin of the os ilium is unequal, and divided into 
two portions, of nearly the same length, by a strong, well-marked 
projection, the anterior inferior spinous process, which is placed an 
inch and a-half below the anterior superior, and gives origin to the 
rectus femoris. This margin joins with the pubes by a large flat- 
tened elevation, called the ilio pectineal protuberance. Between 
the latter and the anterior inferior spinous process, a concavity 
exists which is occupied by the junction of the psoas magnus and 
iliacus internus muscles, where they pass under Poupart's ligament. 
Between the two anterior spinous processes is another concavity, 
from which the anterior edge of the gluteus medius arises. 

The posterior margin of the ilium is also very unequal, both in 
its direction and thickness. The posterior infeiior spinous process 
is about sixteen lines below the posterior superior, and terminates 
a cutting edge running between these two processes. Just below 
it we find the deep excavation called the sciatic notch, through 
which pass out the pyriform muscle, the sciatic nerve, and several 
blood vessels. 

The exterior face of the ilium, called its dorsum, is generally 
convex and rounded ; its margins, however, are so elevated, that 



130 SKELETON. 

partial depressions, or sinkings below the general surface, may be 
remarked, especially at its back part. Just above the two poste- 
rior spinous processes, a flatness is observable, from which a part 
of the gluteus magnus arises. A semicircular rough ridge begins 
at or near the anterior superior spinous processes, and may be 
traced on this surface of the bone to the sciatic notch. All that 
portion of the dorsum between this ridge and the spine, with the 
exception of the little flat surface just above the posterior spinous 
processes, gives origin to the gluteus medius. The dorsum termi- 
nates below at the acetabulum, and between the latter and the 
semicircular ridge is the surface for the origin of the gluteus 
minimus. 

The internal face of the ilium, or that which looks towards the 
belly, is called its costa or venter. Its superior part, amounting 
to about two-thirds of the whole surface, is very concave, and is 
the iliac fossa, which is occupied by the iliacus internus muscle. 
The fossa is continued forwards into the hollow below the anterior 
inferior spinous process, and over the acetabulum. The iliac fossa 
is terminated below by a rounded ridge, a part of the linea ilio- 
pectinea that separates the greater from the lesser pelvis. The 
remaining third of the costa of the ilium is very rough and unequal, 
and is appropriated to the articulation with the sacrum, and to the 
origin of some of the muscles of the back. Immediately posterior 
to the sciatic notch is the surface for the sacrum, which is some- 
what triangular, but irregularly so, and extends from the iliac fossa 
to the posterior inferior spinous process. Behind the sacral sur- 
face is another, twice as large, strongly marked by its roughness, 
and elevated into a vertical ridge at its middle. Anterior to this 
ridge arise many of the ligamentous fibres, fastening the ilium to 
the sacrum ; but posterior to it is the surface of origin to the mul- 
tifidus spina?, and the sacro-lumbalis muscle. 

Os Pubis, (Pubis.) — This bone constitutes the fore part of the 
innominatum, and is much the smallest of the three. It is com- 
posed by a body and two large branches from it, one running 
downwards to join the ischium, and the other backwards and up- 
wards to join the ilium. 

The body of the pubes is joined to its fellow on the opposite side 
by a flat surface, called the symphysis, which is eighteen or twenty 
lines in its long diameter. The superior part of the body also pre* 



OSSA INNOMINATA. 131 

sents a flat surface, called its horizontal portion, which is bounded 
outwardly by the spinous process about an inch from the symphy- 
sis. The horizontal portion and the symphysis form a right angle. 
From the exterior face of the spine two ridges proceed outwardly ; 
the posterior is the crista ; it is frequently sharp, elevated, and 
makes the anterior half of the linea ilio-pectinea ; the anterior ridge 
is lower down, increases in its elevation as it goes along, is 
rounded, and runs nearly horizontally to terminate in the anterior 
upper margin of the acetabulum. Between the two ridges is a 
superficial triangular concavity occupied by the origin of the pec- 
tineus muscle ; the base of the triangle is bounded by the protube- 
rance formed at the junction of the pubes, and ilium, and it is 
exactly over this part that the femoral vessels pass ; its apex is 
the spine or spinous process of the pubes. The extremity of the 
upper branch of the pubes is triangular, and much enlarged where 
it contributes to the acetabulum. 

The inferior branch of the pubes, technically called its ramus, is 
a flattened process about an inch in length, and, as mentioned, 
descends to join the ischium. Its exterior is plain, and has no mark 
deserving of attention ; but the internal face, near the anterior 
margin, is concave for attaching the crus of the penis or of the 
clitoris. 

The body of the pubes in front is concave, and gives origin to 
the adductor longus and brevis muscles ; behind, it is only suffi- 
ciently concave to participate in the general concavity of the pelvis. 

Os Ischium, (Ischion.) — This bone forms the posterior inferior 
portion of the os innominatum, and is the next in size to the ilium. 
It is of a triangular form, and has the anterior extremity bent up- 
wards to join with the pubes. The latter part is its crus or ramus, 
and the remainder is its body. 

The body of the ischium is a triangular pyramid, the internal side 
of which is smooth and uniform, but the posterior and the external 
sides are very unequal. The internal side is broad above and 
narrow below; at the middle of its posterior margin is the spinous 
process, a projection of considerable magnitude, and sharp-pointed, 
for attaching the lesser sacro-sciatic ligament. Immediately below 
the spinous process is a smooth concave surface, forming a trochlea, 
over which the obturator internus muscle plays. Below this trochlea, 
and forming the most inferior internal margin of the bone, is a long 
ridge, somewhat more elevated behind than in front, into which the 



132 



SKELETON. 



great sacro-sciatic ligament is inserted. The internal face of the 
ischium, though technically called its plane, departs from the perfect 
regularity implied in that name, by participating in the general con- 
cavity of the pelvis. 

The posterior face of the ischium is swollen out, above, into a 
rounded surface, for the strengthening the posterior parietes of the 
acetabulum. This swell is bounded, below, by a transverse de- 
pression or fossa; immediately below which, is the tuberosity of the 
ischium, a large rough surface extending from the fossa to the 
beginning of the crus. This rough surface is subdivided into four, 
two above, and two below. The one above, which is external, and 
nearest to the acetabulum, gives origin to the semi-membranosus 
muscle ; the other, which is internal, gives origin to the semi-tendi- 
nosus, and to the long head of the biceps flexor cruris. Of the two 
flat surfaces below, the one which borders on the ridge for the inser- 
tion of the great sacro-sciatic ligament, is the part on which we sit, 
and the last surface, which is exterior again to this, gives origin to a 
part of the adductor magnus muscle. 

The exterior face of the ischium, above, forms the lower part of 
the acetabulum, and is, therefore, very much excavated ; below this 
the surface is flat, and sufficiently uniform to dispense with a parti- 
cular description. 

The crus of the ischium is flattened internally and externally, and 
in the adult it is fused completely into the crus of the pubes, so that 
very faint marks of their primitive separation are left. The anterior 
margin of the crus has, for the origin of the crus penis and the erector 
penis muscle, an excavation continuous with that on the crus of the 
pubes. 

In examining the general features of the os innominatum, it will 
be observed, that its outline is in some degree like the figure 8 ; the 
narrowing in its centre being produced by the sciatic notch below, 
and by the deep concavity above, between the anterior superior 
spinous process and the symphysis of the pubes. The regularly 
rounded margin of the ilium above, and of the ischium below, con- 
tribute to the resemblance, but the angle of the pubes interrupts it. 
The narrowest part of the bone, or its neck, is between the top of 
the sciatic notch and the fossa below the anterior inferior spinous 
process. It will also be remarked, that the posterior margin of 
the sciatic notch is formed by the ilium, and the anterior by the 
ischium. 



THE PELVIS. 133 

The acetabulum, or the cotyloid cavity, (cavite cotyloide,) is 
placed immediately on the outside of the neck of the os innomina- 
tum. In infancy one-fifth of it is seen to be made by the pubes, 
two-fifths by the ilium, and two-fifths by the ischium. It is a very 
deep hemispherical depression, having a sharp elevated margin all 
around, particularly at its superior part. The inferior margin, 
amounting to one-eighth of the whole circumference, is compara- 
tively shallow, and is, indeed, converted into a notch, sunk much 
below the general surface of the brim. The greater part of the ace- 
tabulum is smooth, and incrusted with cartilage wherever the head 
of the os femoris is applied to the support of the trunk ; but the very 
bottom, with the intervening surface continuous with the notch, 
amounting to rather more than one-fourth of the whole cavity, is 
rough, sunk below the general concavity, and is occupied by a soft 
vascular fat. 

In the fore part of the innominatum a large deficiency, called the 
thyroid foramen, (foramen thyroideum,) exists between the pubes 
and ischium. In the male subject it is triangular, with the angles 
rounded ; but in the female it is rather oval. Leading from the 
plane of the ischium is a groove, which goes along the superior end 
of the foramen, and appears externally under the anterior ridge of 
the pubes. It conducts the obturator vessels and nerve to the inner 
side of the thigh. 

The texture of the os innominatum is cellular internally, with a 
condensed lamella externally. It is of very various thickness. The 
ilium, in its centre, has the external and internal sides so near one 
another, that in most adults the light will shine through it. A large 
foramen is seen on the venter of the ilium, and another on its dorsum, 
for the transmission of nutritious arteries. There are several others, 
smaller, at various points of the os innominatum, for the same pur* 
pose, and for the adhesion of ligamentous fibres. 



SECT. V. OF THE PELVIS GENERALLY.- 

The sacrum and coccyx behind, and the ossa innominata at the 
sides and in front, constitute, as observed, the whole cavity called 
pelvis, (bassin.) Its position is such, that, in the adult, it divides the 

Vnat. Atlas, Figs. 33, 34; 
Vol. I.— 12 



134 SKELETON. 

entire length of the body into two parts nearly equal, the head and 
trunk forming one part, and the lower extremities the other. Ge- 
nerally, the former are somewhat the longest ; but in cases of unusual 
corporeal stature, the excess depends upon an undue length of the 
inferior extremities. On the contrary, in persons of little height, the 
latter have not been developed in proportion to the trunk of the 
body. 

The pelvis, as a whole, is a conoidal cavity, having its base up- 
wards, and the summit below. Its internal surface forms an irre- 
gular floor, on which the viscera of the abdomen are sustained in (he 
erect position ; and its external surface, by projecting considerably 
at various places, establishes very favourable points for the attach- 
ment of muscles. 

The internal surface of the pelvis is divided by the projection of 
the anterior margin of the base of the sacrum, and by the linea ilio- 
pectinea, into two cavities ; the upper one is the great pelvis, and 
the lower one the little pelvis. The great pelvis is the base of the 
cone, and presents at its anterior part a large deficiency, which is 
supplied in the fresh subject by the abdominal muscles. The little 
pelvis is a complete bony canal, much deeper behind and at the sides, 
than in front. Its depth, behind, is formed by the whole length of 
the sacrum and coccyx ; at the sides by the bodies of the ischia and 
a small part of the ilia ; and, in front, only by the length of the bodies 
of the pubes, 

The upper orifice of the lesser pelvis is called its superior strait : 
it is somewhat oval, and looks obliquely forwards and upwards. Its 
axis may be indicated by a line drawn from the extremity of the 
coccyx to a point, an inch, or thereabouts, below the umbilicus. 
The inferior orifice of the lesser pelvis is called the inferior strait. 
Its margins in the naked skeleton are very unequal, for it presents 
three very deep notches, two lateral, and one in front. The first 
are formed by the external margins of the sacrum and coccyx, con- 
tributing to deepen the sciatic notch, which already is formed in 
each innominatum. The third one is formed by the convergence 
of the rami of the pubes and ischia of the opposite sides, and con- 
stitutes the arch of the pelvis of authors, sometimes called the arch 
of the pubes. The axis of the lower strait, it is clear, must have a 
very different direction from the axis of the superior, and is indi- 
cated by a line drawn from the lower part of the first bone of the 
sacrum, through the centre of this opening. The cavity of the lesser 



THE PELVIS. 135 

pelvis is increased considerably behind, by the curvature of the 
sacrum ; this, however, is not uniform, as the sacrum is much more 
curved, as well as longer in some individuals than in others. The 
planes of the ischia are not parallel with one another, but converge 
slightly from above, in consequence of which the transverse diameter 
of the lower straight, is rather smaller than the transverse diameter 
of the superior strait. 



Difference of the Pelvis between, the Male and Female. 

There are several well-marked peculiarities in the fully developed 
pelvis of either sex. 

The ossa ilia are larger, less concave, and more horizontal in the 
female. The superior strait is also larger, and more round: its trans- 
verse diameter always exceeds the antero-posterior ; whereas of the 
two, the latter, in the male, is generally found the longer. The lesser 
pelvis is also more capacious in women. The crura of the pubes 
and ischia, are not so long as in men ; but they diverge more, and 
join at the under part of the symphysis pubis by a large, regularly 
rounded arch ; whereas, in men, the arch, as it is called, is merely 
an acute angle. 

The os sacrum in women is shorter, more concave ; and is also 
broader in proportion to its length. The spaces, vertically, be- 
tween its foramina in front are very small, forming ridges, which 
give to the bone the appearance of having been compressed in its 
length. 

The distance between the upper and lower straits, or in other 
words, the depth of the small pelvis in women, is not so great as 
in men : this arises from the comparative shortness in the length of 
the pubes, of the ischia, and of the sacrum, as just mentioned. The 
cartilaginous joining of the pubes is thicker in women. The dia- 
meters of the inferior strait, like those of the superior, are longer in 
females. 

Accoucheurs have attached much importance to the direction 
and length of the diameters of the small pelvis in well formed women. 
At an average they are as follow. The superior strait presents three 
diameters: The first or antero-posterior extends from the upper 
extremity of the symphysis pubis, to the middle of the projection of 
the sacrum at its superior margin, and measures four inches : The 



136 SKELETON. 

second diameter, or the transverse, crosses the first at right angles, 
and extends from the middle of one side of the strait to the corres- 
ponding point on the other ; it measures five inches : The oblique 
diameter extends from the sacro-iliac junction of one side to the linea 
ilio-pectinea over the acetabulum of the other, and measures four 
inches and a-half, sometimes more.* 

At the inferior strait, the antero-posterior diameter is from the 
lower part of the symphysis pubis to the lower end of the sacrum, 
and measures five inches. f As the coccyx, in child-bearing women, 
is moveable, its projection forwards is not taken into the account, 
because it recedes by the pressure of the child's head, and does not 
resist its passage : in some cases, however, it is unfortunately fused 
into the sacrum, and therefore perfectly rigid, which will diminish 
this diameter at least an inch. The transverse diameter of the 
inferior strait is drawn from the middle of the internal margin of the 
tuberosity of one ischium, to the corresponding point on the other, 
and measures four inches. 

The depth of the little pelvis, in the female, at the symphysis 
pubis, is an inch and a-half; at the posterior part four inches, or 
five if we include the coccyx ; and at the side three inches and a- 
half. There are many other details connected with the measure- 
ments of the pelvis, which are mentioned by systematic writers on 
midwifery. 



SECT. VI. DEVELOPMENT OF THE PELVIS. 

Three points of ossification are observable in the os innominatura of 
the early foetus : one is at the superior part of the ilium, another is 
at the tuberosity of the ischium, and the third is at the angle of the 
pubes. The radii of ossification from these centres, have extended 
themselves considerably at birth, so as to sketch out the forms of the 
bones to which they respectively belong. But these bones are 
separated from one another by cartilage, and do not coalesce till 
years afterwards. The union or fusion of the ilium and pubes then 
occurs at theilio-pectineal eminence, over the acetabulum, and partly 
in this cavity : the ilium and ischium join in the acetabulum princi- 

* See Dewees' System of Midwifery, 7th edition, 1835, p. 28. 
f Dr. Dewees says four. Loc. cit. 



THE PELVIS. 



137 



pally, and the ischium and pubes unite by their respective crura at 
the middle of the internal side of the thyroid foramen. All the points 
of the os innominatum, most remote from the primitive centres of 
ossification, are cartilaginous at birth : as, for example, the crest, the 
spinous processes, the tuberosity, and even the component parts of 
the acetabulum. The latter cavity has then a triangular shape, and 
from its very flexible and yielding condition, is incapable of affording 
a strong point of support to the trunk in the erect position. 

At birth, the middle parts of the os sacrum, which are employed 
in protecting the spinal marrow, are more advanced in their ossifi- 
cation than its lateral parts. The five pieces which compose it, are, 
like the bodies of the true vertebrae, of a rounded shape. The pro- 
cesses behind are cartilaginous. The coccyx is extremely small, and 
scarcely presents any ossification whatever. 

The pelvis of theVcetus, at birth, is smaller in proportion than the 
superior portions of the trunk; this is one of the reasons why the 
abdomen is so projecting. The lesser pelvis is so small and shallow, 
that the bladder, even in the undistended state, cannot be accom- 
modated by it, but is contained principally by the abdomen. Its 
transverse diameter is much shorter than the others. The superior 
strait faces much more forwards than in the adult. 



SECT. VII. — ON THE MECHANISM OF THE PELVIS. 

The pelvis has an important part in the several actions of standing 
and of locomotion ; besides its usefulness in giving a support to the 
viscera of the abdomen, and in having attached to, and contained 
within it, the organs of generation. 

In standing, the pelvis is impelled by two opposing forces, in con- 
sequence of the attachment of the vertebral column at its hind part, 
and of the ossa femorum at its anterior lateral parts. The weight of 
the head and of the upper parts of the body, falling upon the sacrum, 
acts upon a lever, which is represented by the distance between the 
acetabula and the sacro-iliac junction, and has a tendency to depress 
the posterior part of the pelvis, by rotating it upon the heads of the 
thigh bones. This movement is obviated by the iliacus interims, 
psoas magnus, and some other muscles, which keep the front of the 
pelvis from rising up. It is also prevented by the principal weight 
of the trunk being in front of the spine, and therefore inclining for- 

12* 



i: 



SKELETON. 



wards, so that the centre of gravity, in the erect position, gives a 
continual tendency to fall forwards instead of backwards. 

The wedge-like shape of the sacrum is highly favourable to the 
erect position : from having its base upwards, whenever the weight 
of tire trunk is thrown upon it, it is driven down between the ossa 
innominata, and has the tightness of its articular connexion, there- 
fore, much increased by the position which it is intended to sustain. 
In illustration of the usefulness of the triangular or wedge-like shape 
of the sacrum, it may be observed, that it is much less so in animals 
which are intended to go upon all fours, than in the human subject. 

The articulation of the several bones of the pelvis with each other, 
is so close as not to admit of any motion between them, with the 
exception of the os coccygis, and of the relaxation peculiar to preg- 
nancy. The pelvis, however, has upon the spine, flexion, extension, 
lateral inclination, and rotation ; the latter being performed by a 
series of very slight twists of the lumbar vertebrae upon each other. 
Like all other motions, it is much extended by habit in early life. 
Of this I have seen an instance, in an adult Indian, who, from in- 
fancy, had been deprived entirely of the use of the lower extremities; 
but who, by being seated in a large wooden bowl, with a round 
bottom, and having his legs drawn up in a squatting position, could, 
by alternate twists of the spine, with the assistance of a short stafTin 
each hand, move with surprising speed over a plain surface. 



SECT. Vffl. — OF THE THORAX.* 

The thorax is the upper part of the trunk, and is formed by the 
dorsal vertebrae behind, by the sternum in front, and by the ribs with 
their cartilages at the intermediate spaces. It is of a conoidal figure, 
flattened in front, somewhat concave behind, and semi-cylindrical 
on the sides. The interior circumference corresponds with the ex- 
terior, with the exception of the posterior part, where, owing to the 
projection of the column of dorsal vertebrae, a partial septum exists 
which has a tendency to divide it into two chambers. The superior 
part of the cone, or its summit, is much smaller than the inferior part 
or the base, and presents a very oblique cordiform foramen, much 
lower in front than behind, owing to the superior margin of the ster- 

* Anat. Atlas, Fig. 35. 



THE THORAX. 139 

num being lower than the first dorsal vertebra. The base of the 
thorax is a very large opening: its lateral and posterior margins, 
formed by the ribs and their cartilages, present a convexity down- 
wards; but, in front, where the latter run up to join the sternum, a 
large notch is formed between the cartilages of the opposite sides, 
into the apex of which notch the third bone of the sternum projects. 



Of the Ribs* 

The ribs, (costce, cotes,) are twenty-four in number, twelve on 
either side. Of the latter, the upper seven, in consequence of their 
cartilages joining the sternum, are called the sternal or true ribs, 
and the lower five, from their cartilages stopping short of the ster- 
num, are called the false or asternal ribs. Cases are recorded by 
several anatomists of there being eleven or thirteen ribs on a side : 
the latter I have seen several times, and the former but once or 
twice. In such cases, the dorsal vertebrae correspond in number 
with the ribs. In the instances of redundance which have come 
under my notice, the last rib looked like a transverse process of un- 
usual length, belonging to a lumbar vertebra. The superabundant 
vertebra constituted the thirteenth dorsal; but was formed like the 
first lumbar as it commonly exists, and the last lumbar vertebra was 
anomalous in its shape, being intermediate in form to a lumbar ver- 
tebra, and to the first bone of the sacrum. 

All of the ribs are so placed, that they run very obliquely downwards 
and forwards from their posterior extremities. This obliquity be- 
comes the more striking as the ribs increase successively in length. 
The first rib, for example, articulating by its posterior extremity with 
the first dorsal vertebra has its anterior extremity nearly on a hori- 
zontal line with the lower part of the third dorsal vertebra. The se- 
venth rib has its anterior extremity on a horizontal line with the lower 
margin of the last dorsal vertebra, notwithstanding its posterior ex- 
tremity articulates with the seventh dorsal vertebra. The same sort 
of comparison might be usefully instituted in regard to all the ribs, 
in which case the rule will be found closely applicable, with the slight 
exception of the two or three last ribs. The ribs are nearly parallel 
to each other in this obliquity, allowance being made for the effect 

* Anat. Atlas, Figs. 3G, 37. 



140 SKELETON. 

which the obliquity of the sternum has in causing a greater separation 
of their anterior extremities from each other, than exists at their pos- 
terior extremities. 

Common points of resemblance between the Ribs. — Each rib is pa- 
raboloid ; presents an external and an internal surface ; an upper and 
a lower margin ; a sternal and a vertebral extremity. 

The external surface of each rib is convex, while its internal sur- 
face is concave. The former presents, not far from the vertebral 
extremity, an oblique ridge, occasioned by the insertion of the sacro- 
lumbal muscle. It is precisely at this line that a curvature some- 
what abrupt, takes place, which is the angle of the rib. Between 
the angle and the transverse process of the vertebra, each rib is rather 
more narrow and cylindroid than it is in advance of the angle. The 
superior margin of the rib is rounded and somewhat rough, for the 
insertion of the intercostal muscles, while the inferior margin is 
brought to a thin, cutting edge. Just within, and above the latter, 
is a fossa beginning somewhat nearer to the spine than the angle of 
the rib, and ceasing about one-third of the whole length of the rib, 
short of its anterior extremity. It contains the intercostal vessels and 
nerve. From the upper margin of this fossa arises the internal inter- 
costal muscle, and from the lower the external. 

The anterior extremities of the ribs are thin and flattened, in the 
upper eight there is some increase in their breadth at this point, and 
in all there is an oblong pit for receiving the end of the corresponding 
cartilage. The vertebral extremity of the rib is its head, and presents 
two flat articular surfaces, separated by a ridge. This head is re- 
ceived into the inter-vertebral matter, and upon the articular faces 
of the adjoining margins of two vertebra?. A small depression exists 
upon the posterior face of the rib bordering on its head, for containing 
a little fatty mass. About an inch beyond the head, at the posterior 
under surface of the rib, is a tubercle, presenting a smooth articular 
face, for connecting itself with the transverse process of the vertebra 
below. Just beyond this, but bordering on it, is a much smaller 
tubercle, not unfrequently indistinct, for. the insertion of the external 
transverse ligament, and below it is a small pit for the lodgment of 
fatty matter near the joint. The space between the first or greater 
tubercle and the head of the rib is its neck, which is in contact 
with the antero-superior face of the transverse process of the ver- 



THE THORAX. 141 

tebra below, and has a sharp ridge on its upper margin, for the inser- 
tion of the internal transverse ligament. 

The most of the ribs have a very sensible twist in them, by 
which their spinal extremity is directed upwards, and the sternal 
extremity downwards ; from which it results, that the whole length 
of the rib cannot be brought into contact with a horizontal plane. 

Differences of Ribs. — Though there are many common points of 
resemblance among the ribs, yet there are, also, some well marked 
peculiarities. Thus the ribs increase successively in length from the 
first to the seventh inclusively; they then decrease by the same rule: 
the last is not only the smallest, but not unfrequently the shortest. 
The angles of the ribs increase in their distance from the spine, from 
the first to the last rib. The angle, however, of the first rib, is not 
well marked, from its being so near the tubercle; neither is the angle 
of the last, from its being so near the anterior extremity. The 
oblique ridges constituting or marking off the angles, are placed one 
above the other, in the same line. This gives to the back of the 
thorax a triangular flatness, the base of which is below. The pro- 
jection backwards of the angles of the ribs, along with that of the 
spinous processes of the vertebras, forms on each side of the latter 
the gutter, which is filled up by the large muscles that keep the trunk 
erect. This gutter is, of course, broader below. 

The first rib is more circular than the others. Its head is hemi- 
spherical, instead of presenting two articular surfaces. This rib is 
flat above and below ; its margins are internal and external. It has 
no groove for the intercostal vessels and nerve. About the middle, 
the upper surface is marked by a superficial oblique fossa, made by 
the subclavian artery; in front of, and behind which is a small 
rising:, marking the insertion of the scaleni muscles. The second 
rib is considerably longer than the first, and has its flat surfaces 
obliquely upwards and downwards, so as to round off that part of 
the thorax. The four inferior ribs decrease at their anterior extre- 
mities, or become somewhat tapering. The last two ribs do not 
articulate with the transverse processes, and, consequently, have no 
corresponding tubercles. As their heads articulate with the middle 
of the bodies of their respective vertebras, instead of with the 
margins, they present only a single and somewhat convex surface. 
The eleventh rib is marked only for a short distance in its middle 



142 SKELETON. 

by the fossa, for the intercostal vessels. The twelfth rib has no mark 
of the kind. 

There is an augmentation in volume from the second to the eighth 
rib, inclusively ; afterwards they decrease. The angles of the ribs 
are, successively, more and more obtuse. 

The structure of the rib is spongy, covered with a lamella of com- 
pact bone. The spongy structure predominates at the anterior ex- 
tremity, for there the rib is comparatively soft. 



Of the Sternum* 

This bone constitutes the middle front part of the thorax, and, 
owing to the obliquity of the ribs, has its superior end on a hori- 
zontal line with the third dorsal vertebra, while its inferior ex- 
tremity is on a horizontal line with the eleventh dorsal vertebra. It 
is also placed in a slanting direction, so that the lower part recedes 
from the spine much farther than the upper. 

The sternum is oblong, somewhat curved, like a bow, so as to be 
convex in front, and concave behind. It is divided, in the adult, 
into three distinct pieces ; an upper, middle, and lower, which are 
held together by cartilage and by ligament ; but not unfrequently in 
advanced life these pieces are all fused into one, by bony union. 
The first and middle parts join where the second rib is articulated, 
and the middle and lower where the seventh rib articulates. At 
these points there is a well marked transverse ridge, both anteriorly 
and posteriorly, and between them on the front of the bone, there 
are other ridges not so strong indicating the original separation of 
the bone into several other distinct pieces. The lateral margins of the 
sternum are somewhat elevated where the ribs articulate. 

The upper end of the sternum is both thicker and broader than 
the lower end. Where the first and second parts join, there is a 
narrowing of the two : the same occurs where the second and third 
pieces unite. 

The first or upper bone of the sternum, has an irregular square 
figure ; it projects somewhat above, and is slightly hollow below. 
It is scooped out at the superior margin, and presents a point at 

* Anat. Atlas, Fig. 38. 



THE THORAX. 143 

each end of the scoop. At the side of the latter is a concave and 
rounded surface, for articulating with the clavicle ; just below which 
is a rough surface, for the cartilage of the first rib. The bone di- 
minishes much in breadth from this point, and terminates by a nar- 
row oblong face, joining it to the second piece. At each side of 
this junction both pieces contribute to a fossa for the cartilage of the 
second rib. 

The second bone of the sternum is longer and narrower than the 
first. At its lower part it increases somewhat in breadth, and then 
terminates by being rounded off on either side, so that its margins 
converge towards each other. The sides of this piece afford complete 
pits for the third, fourth, fifth, and sixth ribs ; the pit for the seventh is 
common to it and the third bone, as the pit for the second rib is 
common to it and the first bone. The sixth and seventh pits are in 
contact, the fifth is very near the sixth, the fourth is about half an 
inch above the fifth. On viewing the whole side of the sternum, it 
will be observed that the distances between the pits decrease, suc- 
cessively, from the first to the last. 

The third bone of the sternum, in the young adult is frequently 
in a great degree or w r holly cartilaginous, hence the name of xyphoid 
cartilage (cartilago xyphoides or ensiformis) has been applied to it. 
It is thin, varies remarkably in its breadth in different individuals, 
and has the lower extremity sometimes turned fonvards and some- 
times backwards, but most frequently it is inclined only slightly for- 
wards. The base of this piece presents a narrow oblong surface for 
articulating with the second bone, at each end of which is the half 
fossa for the seventh rib. The margins of the ensiform cartilage 
are thin, and have the transverse muscles of the abdomen inserted 
into them. Sometimes the lower extremity instead of being pointed, 
is bifurcated. 

The sternum is composed of a spongy texture, enveloped by a 
thin layer of compact substance. Its strength depends, in a great 
degree, upon its ligamentous covering. 



144 



SKELETON. 



SECT. IX. — OF THE CARTILAGES OF THE MBS. 

These are placed at the anterior extremities of all the ribs, the 
seven superior of which they unite to the sternum by the sychon- 
drosis articulation. The length, breadth, and direction of these 
cartilages are far from being uniform. 

The first costal cartilage is short ; the following ones increase in 
length, successively, to the seventh inclusively. The cartilages of 
the false or abdominal ribs decrease, successively, in length from 
the eighth to the twelfth, inclusively ; the last is a mere tip to the end 
of the rib. The breadth of the first cartilage is considerable near 
the sternum ; the succeeding ones are not so large at this point. 
With the exception of the first three, the costal extremities of the 
cartilages are larger than the sternal ; and they become more rounded 
as they advance to the latter. The cartilages, in point of magnitude, 
generally, will be found in proportion to the size of the ribs with 
which they articulate. The sixth and seventh, at their middle, are 
joined together and spread out, which gives there an increase of 
breadth, and permits them to touch, and sometimes to coalesce. 

The first cartilage goes obliquely downwards in the direction of 
the rib to which it belongs, in order to join the sternum. The 
second and the third cartilages are nearly horizontal, but inclining 
a little upwards in their progress ; the fourth, fifth, sixth, and seventh, 
pass, successively, more and more obliquely upwards to the sternum, 
in consequence of the increasing length of the ribs requiring them 
to traverse a longer space to reach this bone. From the direction 
of the cartilages being obliquely upwards, while that of the ribs 
is obliquely downwards, the angle formed near the rib at the base of 
the cartilage, where the latter begins first to turn upwards, is less 
obtuse in the lower cartilages than in the upper. The obliquity of 
these cartilages is also very manifest, by comparing them with the 
side of the sternum : with it they form a very acute angle below, and 
a very obtuse one above. 

The cartilages of the false ribs, as they decrease successively, in 
length, terminate in front by small tapering extremities. The first is 
united by ligaments, somewhat closely, to the last true or sternal, 
and is occasionally sent forward fully to the sternum. The others 
are united more loosely, in such a way that the anterior extremity 



CARTILAGES OF THE RIBS. 145 

of the one lies against the inferior margin of that which is above. 
The eleventh and twelfth cartilages are generally each too short to 
touch the one above it, they therefore are fixed principally by a con- 
nexion with the abdominal muscles. Their ribs are much more move- 
able than any others and have been called floating, from that cause. 

There is some difference between the two extremities of the car- 
tilages ; the posterior or costal is a small, convex, unequal surface, 
very closely united to the anterior extremity of the corresponding- 
rib. The other or sternal extremity in the sternal cartilages, offers 
a smooth articular face, which is angular or convex, according to 
the shape of the cavity in the sternum, with which it has to arti- 
culate. The first three asternal, and the last sternal cartilage, make, 
to the lower part of the thorax, a broad and well marked margin, 
convex in front and concave behind. 

The cartilages of the ribs are, in persons of middle age, white, 
flexible, and very elastic. They are dissolved very slowly in boil- 
ing water ; by which they, if young, are reduced to gelatine, other- 
wise their solubility is very imperfect. They have a structure differ- 
ing, in some respects, from other cartilages; when dried, and 
exposed to the action of the atmosphere, they are seen to consist of 
an immense number of small thin plates, placed face to face, and 
separated by deep fissures. M. Herissant describes these plates as 
interlaced one with another, and forming a kind of spiral, the re- 
gularity of which is interrupted by small cartilaginous projections, 
uniting the plates to each other.* These cartilages have a great 
disposition to ossify, which is manifested in most individuals some- 
what advanced in life. The ossification begins in their centre, and 
advances to the circumference, and is always preceded by a yel- 
lowish tinge. When they are fully ossified, like the ribs, they are 
cellular widiin, and compact externally, and are continuous with the 
ribs, there being no interval : in such cases, the distinction from the 
sternum is generally kept up by the preservation of the joint, with 
the exception of the first, which is fused into it. The complete 
ossification of the first cartilage is not uncommon; the others, 
though there is generally in old persons a considerable deposite of 
bone in them, are seldom fully ossified. In neither case, however, 
is it common to see such a perfect continuity of bone between the 
rib and sternum, that the junction may not be dissolved at one 

* Acad, des Sciences, an. 1748. 
Vol. I.— 13 



146 



SKELETON. 



point or another of this space by the action of boiling water ; at 
least, after very numerous observations on this subject, I do not re- 
member to have met with a single instance of it. 



SECT. X. OF THE DEVELOPMENT OF THE THORAX. 

In the foetus the shape of the thorax differs much from that of 
the adult, in the greater comparative extent of its antero-posterior 
diameter, and in the projection of the sternum. The state of the 
thoracic viscera, at this period, calls for such an arrangement ; as 
the heart and thymus gland, which are in the middle, have a con- 
siderable extent ; whereas, the lungs are still collapsed from the 
emptiness of their air cells. The ribs are but little curved at their 
posterior parts, the angle being by no means well formed, in con- 
sequence of which, the fossa on each side of the bodies of the ver- 
tebrae, within the thorax, is not so deep ; neither is the fossa behind, on 
each side of the spinous processes, so fully marked. The superior 
opening of the thorax is more round from the increase of the antero- 
posterior diameter. The inferior opening is extremely large, both 
from the elevation of the sternum, and from the pressure of the ab- 
dominal viscera, of which the liver, from its great extent, is a prin- 
cipal agent. The vertical diameter of the thorax is small, from the 
ribs particularly the lower ones, being pressed up one against the 
other, by the diaphragm, acted on by the abdominal viscera. 

The bones individually are in the folllowing state at birth. The 
ribs are almost completed, the heads where they join the spine, 
being in a state nearly as perfect as at any subsequent period of 
life, and not by any means in the condition of a cartilaginous epi- 
physis; as is presented in the extremeties of the cylindrical bones 
generally. These bones, as Bichat very justly observes, are de- 
stined to a function which commences immediately upon birth, 
and which requires in them as much perfection then, as they have 
in the adult. For respiration is different from locomotion, the lat- 
ter requires a species of education, which may be given gradually, 
whereas one respires from the beginning as he will respire always. 
The sternum, which is less immediately connected with breathing, 
and only contributes to the general solidity of the thorax by com- 



MECHANISM OF THE THORAX. 147 

pleting its circumference, is in a state almost cartilaginous, and 
presents only nuclei of ossification in its several pieces. 

At the instant of birth, a great change is produced in the dimen- 
sions of the thorax. The lungs, from being in a collapsed and 
solid state, suddenly suffer an expansion of their cells by the intro- 
duction of air into them, and increase twice or three times in mag- 
nitude. This is accomplished by the elevation of the ribs, and the 
consequent increase in the transverse diameter of the thorax: it be- 
comes a condition that for ever afterwards remains, so that the lungs, 
even upon death, continue to have their air cells distended, and do 
not return to a perfectly collapsed state. The action of the dia- 
phragm is but small in the earlier periods of life ; owing to the size 
and pressure of the abdominal viscera against it ; respiration is then 
principally carried on by the elevation and depression of the ribs, 
and by their being rolled outwards, a motion which the flexibility of 
their cartilages and the looseness of their articulating surfaces favour 
very much. 

At the age of puberty the thorax experiences a remarkable aug- 
mentation. Its transverse diameter is sensibly increased, and there 
is a general expansion of its volume, indicative of a healthy and 
vigorous constitution. Should this not take place, and the sternum 
be projected, it is supposed to mark a disposition to consumption. 
The enlargement of the thorax is undoubtedly also connected with 
a development of the organs of generation at the same time. The 
exercise of the latter requires greater vital powers than exist in 
early life, and the provision for it is manifested by the general in- 
crease of vigour and firmness in the human frame ; but it is not 
possible to point out in what manner the sympathy exists, which, on 
the development of the organs of generation, extends their influence 
to the bony structure of the thorax. 



SECT. XI. OF THE MECHANISM OF THE THORAX. 

The thorax performs two very important offices in the animal 
machine : the first is to contain and protect the organs of circulation 
and of respiration, the second to assist in the function of respiration, 
and perhaps that of circulation.* 

* A very interesting paper, on this subject, was presented to the French In- 
stitute by M. Barry, some years ago. 



148 



SKELETON. 



The mechanism of the thorax is such that the solidity of its mate- 
rials, and its rounded shape, present a very efficacious defence of 
its viscera, from the influence of blows on its outside. The effects 
of the latter are also materially diminished by the thickness and con- 
traction of the several large muscles which are placed on its surface. 
On its back part the thick longitudinal muscles of the spine, as well 
as those running to the superior extremities, fill up the gutters on 
each side of the spinous processes, and make a fleshy protuberance, 
divided into two by the raphe which extends the length of the back 
over the spinous processes. In front it is less protected, owing to 
the sternum being immediately under the skin. Nevertheless, when 
blows are inflicted on this part, their effects are much diminished by 
the elasticity of the cartilages of the ribs, and by the direction, ob- 
liquely downwards, of the ribs themselves ; both of which dispose 
the sternum to retreat backwards, and to yield to the impelling 
force. The recession will take place more readily at the moment of 
expiration ; and when the muscles w r hich elevate the ribs are not on 
their guard. In those deliberate exertions of the strength of the 
thorax, exhibited by individuals lying down on their backs, and 
sustaining a heavy weight on the sternum, the ribs are saved from 
injury by different means. The arched form, itself, of the front of 
the thorax, is of considerable service in the resistance under such 
circumstances ; this, however, would be easily overcome, and the 
ribs would break, if the arch were not sustained in its elevation by 
the contraction of the large muscles on its sides ; as the serratus 
major, the pectoralis major, and minor, each of which, by acting on 
the depressed anterior extremities of the ribs and their cartilages, has a 
tendency to keep them elevated. Fractures of the ribs, from blows or 
force applied in front, are not so liable to occur in the part stricken 
as in the point feeling the greatest momentum, which from the semi- 
circular form of the ribs is in or near their middle : this exhibits a 
true example of what the French writers call the contre-coup. 
Bichat says, that the fracture by contre-coup is much more com- 
mon when the individual being struck unexpectedly, has not had 
time to throw his muscles into a state of contraction, for the protec- 
tion of the ribs. 

The lateral convexity of the thorax being greater than that in front 
or behind, and having the same assistance from the muscles men- 
tioned, presents a stronger resistance when blows are inflicted 
directly on it. Each rib represents an arch, the submit of which 



MECHANISM OF THE THORAX. 149 

is its centre, and the base its two extremities. The abutments of 
the base are, the sternum at one end and the spine at the other : a 
displacement from them is completely prevented by the strength of 
the ligamentous attachments, as well as by the form of the surfaces. 
Under these circumstances, as fracture occurs preferably to disloca- 
tion, it is generally at the point stricken. 

The abdominal or false ribs, from their want of attachment to the 
sternum, present a very different condition. Their anterior extre- 
mities, therefore, yield readily, and are driven inwards towards the 
abdomen. 

The second function of the thorax, relating to its influence on 
respiration, is executed by its dilating and contracting, whereby the 
air is received into, and expelled from it. The spine is the fixed 
point for the motions of the ribs in respiration. In the act of dila- 
tation, the capacity of the thorax is augmented in three directions, 
vertically, transversely, and antero-posteriorly, or from the sternum 
to the spine. The vertical augmentation is accomplished by the 
diaphragm ; and, as mentioned, is much greater proportionally in 
the adult than in the infant, from the greater comparative size of the 
abdominal viscera in the latter. The transverse augmentation is 
produced by the successive contraction of the intercostal muscles, 
which raise the ribs upwards. The first rib is moved inconsiderably, 
in consequence of its shortness and of its continuity with the sternum. 
The attachment of the scaleni muscles to its upper surface, serves 
rather to give a fixation to it, and to prevent it from being drawn 
down by the other ribs, than to produce by their contraction an ele- 
vation of it. The first rib may, therefore, be considered as a fixed 
point. The first intercostal muscles contracting from it, draw up 
the second rib, which, in its turn, becoming a fixed j->oint for the 
second intercostal muscles, they contract and draw up the third rib, 
and so on successively to the last. It is the obliquity of the ribs 
from behind, downwards and forwards, which enables this elevation 
of them to produce an increase in the lateral diameter of the thorax : 
without such obliquity, their elevation would not have the effect. 
But the obliquity alone could be of but little service, if the anterior 
extremities of the ribs were not attached to the sternum by cartilages, 
which have to ascend in order to reach it ; for it is obvious that the 
angle of the cartilage and rib, during their elevation by the intercostal 
muscles, has a tendency to enlarge itself; and will, in doing so, 

13* 



150 



SKELETON. 



increase the horizontal distance between the anterior end of the rib 
and the sternum, and consequently increase the transverse diameter 
of the thorax. The upper ribs, from the shortness as well as direc- 
tion of their cartilages, can do little or nothing in increasing this 
diameter. 

According to some anatomists, the capacity of the thorax is also 
augmented by a rocking motion of the rib, in which the two extre- 
mities being stationary, the middle is drawn upward and outward. 
It is not, however, very clear, that this motion exists to much extent, 
in the adult, as the posterior articulations of the thorax are opposed 
to it. 

While the transverse enlargement of the thorax is going on, a 
simultaneous motion occurs in the sternum, and in consequence of 
the oblique direction in which the ribs run to it, the sternum is 
caused, by the elevation of their bodies, to recede from the spine. 
But, as the ribs increase successively in length from the first to the 
seventh, each lower one, in its elevation from the oblique towards 
the horizontal line, has its anterior extremity carried proportionably 
farther off from the spine; hence, the sternum has a combined move- 
ment resulting from its several attachments to the ribs: one motion 
elevates it as a whole, another causes it to recede from the spine as 
a whole: and the third causes its lower end, from the increased 
length of the ribs there, to be pushed farther from the spine than the 
upper ; giving it, thereby, during respiration, a slight motion back- 
wards and forwards, resembling that of a pendulum. This latter 
motion, however, though its existence is clear, is not very con- 
siderable, from the sternum being kept in check by the tendinous 
centre of the diaphragm, as one may prove by examining his own 
body. The enlargement of the thorax, in its antero-posterior dia- 
meter, is much more considerable at the anterior extremities of the 
ribs, because there they are comparatively free. In this case, the 
cartilages of the ribs are bent forwards, besides being elevated. 

In expiration, the movements of the thorax are exactly the reverse 
of what they are in inspiration, and all its diameters are, conse- 
quently, diminished. Whatever may be said of muscular influence 
in producing this change, it is much exaggerated. It is true, that 
there are certain muscles which may be applied to this end, as the 
abdominal, and also some on the back, as the longissimi dorsi and 
sacro lumbales ; but that they are actually so engaged, under ordi- 
nary circumstances, is rather questionable. In observing the pheno- 



MECHANISM OF THE THORAX. 151 

mena of natural respiration, when, by position, all these muscles are 
put into a state of relaxation, it does not appear that the process is 
at all impaired by their being thrown out of action. The only mus- 
cles, therefore, that seem to be especially appropriated to produce 
expiration, are few and small : they are the serrati inferiores postici, 
one on either side of the spine. But, when the lower ribs are fixed 
by the several muscles inserted into them, they become points of 
support to the upper ones ; and then the intercostal muscles may 
officiate in expiration, by drawing the ribs successively downwards, 
as they do, in inspiration, by drawing the ribs successively upwards. 
The elasticity of the cartilages, by which these bodies are en- 
abled to return from the constrained state in which they were placed 
by inspiration, has also been supposed important to expiration, by 
Haller, and others. The pow r er thus derived is certainly of some 
value ; but of much less than has been attached to it. It unques- 
tionably exists in early and middle life, but is lost in old age, when 
the cartilages ossify, and, therefore, are of diminished elasticity. The 
true and efficient cause of expiration appears to be atmospheric pres- 
sure, upon the external parietes of the thorax, acting along with the 
natural elasticity of the lungs. The lungs, it is well known, when 
in a state of repose, and removed from the thorax, are much smaller 
than the cavities which they fill during life. They have, therefore, 
a continual disposition, in the living state, to return to the size which 
is most easy to them ; and, when they are dilated by inspiration, 
they subsequently contract. These positions are proved conclu- 
sively, by the condition of the inferior surface of the diaphragm, in 
a healthy and entire thorax ; where this muscle, in consequence of 
atmospheric pressure from without, is driven high up into its cavity. 
Its contraction in inspiration draws it down, and the instant that the 
contraction ceases, it is impelled upwards again. Now, the same 
power is applied to the whole periphery of the thorax: and its ca- 
vity being enlarged by the contraction of the several muscles appro- 
priated to the elevation of the ribs ; the moment this contraction 
ceases, the latter are impelled downwards. From all this it will be 
understood that the muscles, by creating a vacuum in the lungs, 
cause the vacuum to be filled by the introduction of air through the 
trachea; and upon their ceasing to contract, the several agents men- 
tioned cause the expulsion of the same air. It is generally believed, 
that the surface of the lung is every where in contact with the tho- 
rax ; it appears, however, doubtful, whether there is not a space be- 



152 



SKELETON. 



tween the pleura pulmonalis and diaphragmalis, particularly at the 
most posterior and inferior part of the diaphragm. Certain it is, that 
adhesions there, are much less common than in other parts of the 
thorax. 

The ligaments at the spinal extremities of the ribs, by being put 
on the stretch in inspiration, have also some tendency to throw 
down the ribs in expiration. In short, the contraction of the thorax 
may be set down as the result of the joint action of the atmosphere, 
the cartilages of the ribs, the ligaments, the contraction of the lungs, 
and the muscles. When the structure of the lung is so altered that 
its elasticity is impaired or destroyed, expiration becomes then much 
more difficult. 



CHAPTER II. 

Of the Head.* 

The head is placed upon the upper extremity of the vertebral 
column, and consists in a considerable number of bones, which are 
either in pairs, or, if single, have the two sides symmetrical. Some 
of these bones form a large cavity, the cranium, for containing the 
brain ; the others are employed in the formation of the nose; of the 
orbit for the eye-ball; and of the mouth. The head, for the most 
part ovoidal, presents very striking varieties of form between diffe- 
rent individuals and different nations. It is thought by physiolo- 
gists, that the moral or intellectual condition of a people, their 
habits, climate, and food, have a powerful influence in producing 
these diversities. The head is divided into Cranium and Face. 



SECT. I. OF THE CRANIUM. 

The Cranium is composed of eight bones. The Os Frontis, the 
Os Occipitis, two Ossa Parietalia, two Ossa Temporum, the Os 
Sphenoides, and the Os Ethmoides. The Os Frontis is at the 
front of the Cranium; the Os Occipitis is at its hind part ; the Ossa 

* Anat. Atlas, Fig. 53. Also Frontispiece. 



THE CRANIUM. 153 

Parietalia, one on each side, form its superior lateral parts; the 
Ossa Temporum, also one on each side, form its inferior lateral 
parietes ; the Os Sphenoides is in the middle of its bottom part ; 
and the Os Ethmoides is at the fore part of the centre or body of 
the last bone. 

The cavity thus formed for the brain, has three diameters, which 
may be learned by sawing vertically through the middle line of 
one skull, and horizontally through the cavity of another. The 
first diameter is the longest, and extends from the lower part of 
the frontal bone to the protuberance on the middle of the interior 
surface of the os occipitis ; it is commonly about six inches and a 
half long. The second diameter includes the space between the 
superior margins of the temporal bones, where they are most dis- 
tant from each other, and passing over the middle of the great 
occipital foramen, is about five inches. The third diameter is 
taken from the centre of the great occipital foramen to the centre 
of the suture between the parietal bones; it is about five inches, 
also. Rather more than one-third of the cavity of the cranium 
is placed behind the second diameter, and it diminishes some- 
what abruptly ; but in front of this diameter the cavity is finished 
more gradually. 

When the face is separated from the cranium, the exterior sur- 
face of the latter, excepting its base, represents somewhat accu- 
rately the form and proportion of its cavity : allowance being made 
for the large sinuses in the lower part of the frontal bone, and for 
the thinness of the upper parts of the temporal bones. The diame- 
ters mentioned, can only represent what most frequently happens, 
for daily observation proves remarkable departures from them. 
Sometimes the transverse diameter is increased at the expense of 
the longest, which gives to the cranium a flatness before and behind. 
On other occasions, the vertical diameter is increased, whereby the 
cranium receives a conical form. In many individuals the first dia- 
meter is increased, which makes the two sides of the cranium 
more parallel and flat than usual. The elongation of the trans- 
verse diameter is the most common, and that of the vertical the least 
so. The capaciousness of the cranium is much the same in adult 
individuals of the same sex ; from which it may be inferred that the 
excess of one diameter is obtained generally at the expense of the 
other. The male cranium is more capacious and thick than the 
female. 



154 



SKELETON. 



The female sex is less liable to variations in these proportionate dia- 
meters than the male. Stature has but little influence on the capa- 
ciousness of the cranium, \s giants and dwarfs have it of the same 
size ; hence, the former seem to have very small heads, while the 
latter appear to have very large ones, the eye being deceived by the 
relative magnitude of their bodies. 

The fact seems to be now well ascertained, that continued pres- 
sure, or rather, resistance in a fixed direction, made upon the cra- 
nium of a growing infant will change its natural form. Peculiar 
ideas of beauty have induced certain tribes of savages to adopt this 
barbarous and unnatural practice. The late professor Wistar* 
showed to his class, in 1796, a Choctaw Indian having this pecu- 
liarity ; and a tribe now existing near the sources of the Missouri, 
continues the practice of flattening both the occiput and the os 
frontis. 

In the Wistar Museum we have ten headsf of Peruvian Indians, 
brought from the Pacific Ocean, nine of which bear the strongest 
evidence of having been flattened by pressure, on the os frontis and 
on the os occipitis4 The possibility of effecting such a change in 

* System of Anat. 3d edit. vol. i. p. 73, 1824. 

f Presented by Dr. James Corneck, U. S. Navy, to the late Dr. Physick, 
Anat. Atlas, Figs. 39, 40. 

X The following letter, from a distinguished Missionary, the Rev. Mr. De 
Smet, S. J., who had spent some years among the Indians, on the west side of 
the Rocky Mountains, will be read with interest. 

To Professor William E. Horner, M. D. 
The process of flattening the head exists among several tribes on the Colum- 
bia river. Among the Indians at the cascades, and Tchenouks at Fort Van 
Couver, I remarked several babes, who were undergoing the barbarous process. 
They attach them to boards of about two feet in length. This sort of cradle is 
covered with a skin, with the hair outside; the child is stretched on it; its 
little arms are tied close to the body with soft leather bandages ; another skin 
is fastened to each extremity of the board and covers the child. A smooth strip 
of cedar bark, or of other elastic wood, four or five inches broad, is fastened 
over the forehead of the babe, so tight, that the eyes of the infant appear to 
start from their very sockets. In this painful situation, I was told, they have 
them for the space of about a year, after which, the head has taken the form 
they wish to give it, and which they consider as a mark of distinction and of 
great beauty. This deformity in children is very apparent; the forehead 
and the upper part of the head are in a straight line. The deformity disap- 
pears partly as they grow old. These Indians have slaves, who are forbidden, 



THE CRANIUM. J 55 

the form of the cranium has been strongly contested ; and Bichat 
who admits it, acknowledges that he was unable to produce like 
modifications in puppies, kittens, and India pigs. The singular 
change, however, which is wrought upon the feet of Chinese ladies, 
strongly corroborates the opinion of the head being also susceptible 
of artificial modification in its form.* 



SECT. IT. — OF THE INDIVIDUAL BONES OF THE CRANIUM. 

1. Frontal Bone, (Os Frontis, Frontal.]) 

The frontal bone forms the whole anterior, and a portion of the 
superior, lateral and inferior parietes of the cranium. It is sym- 
metrical, and, occasionally, is completely divided into two bones 
by the continuation of the suture between the parietal bones. 

Its external face is convex, and the internal concave. On the 
former may be observed a line, or slightly raised ridge, running, 
on the middle of the bone from above downwards, which is expres- 
sive of the original separation between its two halves. The front 
surface of the bone is terminated on either side, below, by the orbi- 
tary or superciliary ridge, a sharp and arched elevation, forming the 
upper anterior boundary to the orbit of the eye. This ridge termi- 
nates outwardly by the external angular process, and inwardly, by 
the internal angular process. Just above the internal half of the or- 
bitary ridge the bone is raised, by the separation of its tables, into 

under the severest penalty, to flatten the heads of their offspring-. The cascade 
Indians and Tchenouks are remarkable for their ingenuity in constructing con- 
venient and beautiful canoes, nets, and wooden utensils; they are, in no ways 
considered inferior to their round head neighbours. Their constant intercourse 
with the whites has rendered them more vicious, poor and indolent; they are 
much addicted to lying, stealing and immorality. 

P. I. DE SMET. 
Philadelphia, February 10th, 1843. 

* In an examination the author made of an adult female of this nation, 
Among Foy, the measurements were two inches and one-eighth from the heel 
to the end of the small toe; four inches and three-quarters from the heel to the 
end of the great toe; and the circumference of the ankle six inches and six- 
tenths. 

f Anat. Atlas, Figs. 41, 42, 43. 



156 



SKELETON. 



the superciliary or nasal protuberance or boss. Between the internal 
angular processes abroad serrated surface exists, by which the frontal 
bone is united to the nasal bones, and to the nasal processes of the 
superior maxillary bones. The centre of this surface is elevated into 
the nasal spine, which serves as an abutment to the nasal bones, and 
resists any force which might tend to drive them inwards. On its 
exterior lateral surface, behind the external angular process, the 
frontal bone presents a concavity bounded above by a well marked 
semi-circular ridge, and intended for the lodgment of a part of the 
temporal muscle. 

On each side of the front of the bone near its middle a prominence 
exists, most frequently better marked in infancy than in advanced 
life, and called by the French the frontal protuberance, it being the 
original centre of ossification for that side of the bone. 

Proceeding backwards from the inferior part of the bone are the 
two orbitar processes, concave below and convex above. They are 
much thinner than other parts of the bone, and are separated by an 
oblong opening which receives the ethmoidal bone. A depression 
large enough to receive the end of a finger, is at the exterior anterior 
part of the orbitar process, being protected by the external angular 
process: this depression contains the lachrymal gland. Half an 
inch above the lower margin of the internal angular process, a much 
smaller depression exists, occasioned by the tendon of the superior 
oblique muscle where it plays upon its trochlea. In the orbitary 
ridge, just without the latter depression, is the supra-orbitary fora- 
men or notch, for the passage of the supra-orbitar artery and nerve. 
The internal margins of the orbitar processes are broad and cel- 
lular, where they join the ethmoid bone ; and at their fore part 
is seen a large opening on each side leading into the frontal sinus. 
These margins, in common with the ethmoid bone, form two foramina, 
one anterior, another posterior, and called internal orbitary or eth- 
moidal ; the first transmits the internal nasal branch of the ophthalmic 
nerve and the anterior ethmoidal artery and vein, the latter trans- 
mits the posterior ethmoidal artery and vein. Externally and be- 
hind, the orbitar process presents a broad triangular serrated surface 
for articulating with the sphenoid bone. 

The interior or cerebral face of the os frontis is strongly marked 
by depressions corresponding with the convolutions of the brain ; on 
its middle exists a vertical ridge, becoming more elevated as it 



THE CRANIUM. 157 

approaches the ethmoidal bone. This ridge is situated below, ex- 
tends about one-half of the length of the bone, and terminates, above, 
in a superficial fossa, made by the longitudinal sinus of the dura 
mater ; at its lower extremity is the foramen caecum, common to it 
and the ethmoid bone, and which is occupied by a process from the 
great falx of the dura mater, and also affords passage to some very 
small veins, which go from the nostrils to the commencement of the 
longitudinal sinus.* 

The frontal sinuses consist in one or more large cells, placed 
beneath the nasal protuberances. There is a very great variety in 
their magnitude and extent ; sometimes they proceed as far outwards 
as the external angular process, and backwards for half an inch into 
the orbitar plates. In a few instances in the adult they do not exist, 
but the cases are very uncommon. The cells of the opposite sides 
have a complete partition. They communicate with the cavity of 
the nose through the anterior ethmoidal cells. 

With the exception of the inferior part, where the processes and 
sinuses exist, the os frontis is of a very uniform thickness, and the 
diploic or cellular structure is found constantly between its external 
and internal faces. 

This bone is united to the parietal, ethmoidal, and sphenoidal of 
the cranium ; and to several bones of the face. 

2. Parietal Bones, (Ossa Parietalia, Os Parietaux.\) 

These bones, it has been stated, form the superior and lateral 
parts of the middle of the cranium. They are quadrilateral, convex 
externally, and concave internally. Their external and internal 
tables are uniformly separated by a diploic structure, which, from 
being more abundant at the superior part of the bones, occasions 
there an increased thickness. 

The external surface of the parietal bone is raised about its middle 
into the parietal protuberance. Just below this protuberance is an 
arched, rough, broad, but slightly elevated ridge, marking the origin 
of the temporal fascia and muscle, and continuous with the ridge on 
the side of the frontal bone. The internal surface of the bone is 

* Portal. Anat.Medicale. 
f Anat. Atlas, Figs. 44, 4§» 

Vol. I.— 14 



158 SKELETON. 

marked by the convolutions of the brain ; there is also a number of 
furrows upon it, having an arborescent arrangement, and produced 
by the ramifications of the middle artery of the dura mater. The 
furrows all proceed from two large ones at the anterior and at the 
inferior part of the bone : not unfrequently at the latter point they are 
converted into perfect tubes, by the deposition of bone all around the 
arteries. Of the two furrow r s, the foremost may be traced from the 
greater wing of the sphenoidal bone, and running somewhat parallel 
with the anterior margin of the parietal ; and the other passing from 
the squamous portion of the temporal, is commonly a little behind 
the middle of the parietal bone, and inclines towards its posterior 
superior angle. The internal face of the parietal bone also presents 
an imperfect fossa at its superior margin, which is completed by 
junction with its fellow, and accommodates the longitudinal sinus 
of the dura mater. Near this edge it is not uncommon to see one 
or more small irregular pits passing through the internal table, and 
looking somewhat ulcerated: these are formed by the glands of 
Pacchioni, in the dura mater. At the inferior posterior corner of 
the bone, there is also a fossa, which is made by the lateral sinus of 
the dura mater. 

The superior, posterior, and anterior margins of the parietal bone 
are regularly serrated, and nearly straight. The inferior margin is 
concave, presenting a thin, bevelled, radiated surface before, for 
articulating with the squamous portion of the temporal bone : behind 
this concavity, the angle of the bone is truncated and serrated, for 
articulating with the angular portion of the os temporis. The anterior 
inferior angle is the most remarkable, from its being elongated so as 
to join the sphenoid bone in the temporal fossa. 

A foramen, called parietal, is found at the superior margin of this 
bone, nearer to its posterior than to the anterior edge ; it transmits 
an artery between the integuments and dura mater, and also a vein 
from the integuments to the longitudinal sinus. M. Portal says, that 
in some protracted headachs this vein swells considerably ; and that 
he has seen much good in such cases, arise from the application of 
leeches to the part: he has also seen, in a child, its tumefaction the 
precursor of the paroxysms of epilepsy. 

The parietal bone articulates with its fellow, with the frontal, the 
sphenoid, the temporal, and the occipital bones. 



THE CRANIUM. 159 

• 3. Occipital Bone, (Os Occipitis, Occipital * J 

This bone is quadrilateral, resembling a trapezium. It is convex 
externally, and concave internally ; but both of these surfaces are 
much modified by ridges and processes. Its thickness is also very 
unequal ; though like the other bones, it has two tables, with an in- 
termediate diploe. It is so placed as to form a considerable share 
of the posterior and inferior parietes of the cranium. 

The foramen magnum is found in the lower half of this bone, and 
constitutes a very conspicuous feature in it. This hole is oval, the 
long diameter extending from before backwards. Its anterior in- 
ferior margin, on either side, is furnished with a condyle, for arti- 
culating with the first vertebra of the neck. These condyles are 
long eminences tipped with cartilage, which converge forwards, so 
that lines drawn through their length would meet an inch in front of 
the foramen magnum ; they recede behind : their internal margins 
are deeper than their external. The condition of their articular sur- 
faces is therefore such, that they permit flexion and extension of the 
head, but not rotation. The anterior edge of the foramen is thicker 
than the posterior. This foramen transmits the medulla oblongata, 
the vertebral arteries and veins, and the spinal accessory nerves. 

The external surface of the occiput presents, half way between the 
foramen magnum and the upper angle of the bone, the external oc- 
cipital protuberance, from the lower part of which a small vertical 
ridge is extended in the middle line to that foramen. Into the 
ridge is inserted the Ligamentum Nuchas. From either side of the 
protuberance an arched ridge is extended to the lateral angle of the 
bone ; it is the superior semi-circular ridge or line, from which arise 
the occipito frontalis and the trapezius muscles, and into it is inserted 
a part of the sterno cleido-mastoideus. Below this about an inch is 
the inferior semi-circular ridge, more protuberant, but not so dis- 
tinctly marked in its whole course. Into the inner space, between 
the upper and lower ridges, is inserted the complexus muscle, and 
into the outer space between the same, the splenius muscle. The 
lower ridge is principally occupied by the insertion of the superior 
oblique muscle of the neck. 

* Anat. Atlas, Figs. 46, 47. 



160 SKELETON. 

The inner space between this ridge and the great foramen, gives 
insertion to the rectus posticus minor, and the outer space afibrds 
insertion to the rectus posticus major. Into a small elevation, lead- 
ing from the outside of the condyle directly to the margin of the 
bone, is inserted the rectus capitis lateralis. 

In a depression behind each condyle is the posterior condyloid 
foramen, which conducts a cervical vein to the lateral sinus. 
Passing through the base of the condyle, and having its orifice in 
front, is the anterior condyloid foramen for conducting the hypo- 
glossal nerve to the tongue. 

That part of the bone before the condyles is the cuneiform or 
basilar process : the base of which is marked by depressions for the 
insertion of the recti muscles, which are situated on the front of the 
cervical vertebra? ; and its fore part, which is truncated at the end, 
overhangs the pharynx, and is placed against the body of the sphe- 
noid bone. The superior external part of the os occipitis is uni- 
formly convex, being covered by the occipito frontalis. 

The internal surface of the os occipitis is strongly impressed by 
ridges and depressions. On that portion of it behind the great fora- 
men, is a rectangular cross, forming at its centre the internal occi- 
pital protuberance, which is much larger than the external. The 
upper limb of the cross is marked by a fossa for the posterior end of 
the longitudinal sinus ; the two horizontal limbs are also marked, 
each by its respective fossa, which receives the corresponding late- 
ral sinus. The right fossa is frequently the largest. The inferior 
vertical limb of the cross has attached to it the small falx of the dura 
mater, and is slightly depressed by a small sinus. The spaces be- 
tween the limbs of the cross are much thinner than other parts of 
the bone, and present broad concavities, the two superior of which 
receive the posterior lobes of the cerebrum, and the two inferior, the 
lobes of the cerebellum. 

The superior face of the cuneiform process is excavated, longitu- 
dinally, to receive the medulla oblongata. On each side of the fora- 
men magnum, a short curved fossa is observed, which receives the 
lateral sinus of the dura mater just before its exit from the cra- 
nium. 

The two superior margins of the occipital bone are regularly ser- 
rated. The inferior margins have each, in their centre, a process 



THE CRANIUM. 161 

termed the jugular eminence, in front of which is a rounded notch, 
forming a part of the jugular fossa ; this notch is continuous with the 
semi-circular fossa which holds the inferior end of the lateral sinus, 
and transmits the internal jugular vein and eighth pair of nerves. 
The edge of the bone above this eminence is serrated, but below it 
is rather smooth and rounded, being parallel with the temporal bone, 
and having an imperfect adhesion to the petrous part of it, before 
the jugular fossa. 

The occipital bone articulates above with the parietal, laterally 
with the temporal ; and in front with the sphenoidal. 



4. Temporal Bones, (Ossa Tempprum, Temporaux.*) 

These bones form portions of the inferior lateral parietes, and of 
the base of the cranium. 

Their figure is very irregular. Their circular anterior portion is 
called squamous : behind it is the mastoid, and between the others is 
the petrous. 

The squamous portion is thinner than the other bones of the cra- 
nium that have been described, from the temporal muscle and its 
fascia covering it, so as to contribute also to the protection of the 
brain. Its exterior surface is smooth and slightly convex. The in-, 
terior is formed into depressions by the convolutions of the brain. 
At the anterior inferior part of the latter surface, a groove is made 
by the middle artery of the dura mater, immediately after it gets 
from the foramen spinale of the sphenoid bone on its way to the 
parietal. This groove bifurcates, one branch runs backwards to join 
the posterior groove of the parietal bone ; and the other ascends to join 
the anterior groove of the same, frequently, however, impressing the 
top of the great wing of the sphenoid, just before it reaches the pa- 
rietal. The greater part of the circumference of this portion is sloped 
to a sharp edge, but at the anterior inferior part it is serrated and 
thicker. On the outside of the latter is the glenoid cavity, for ar? 
ticulating with the lower jaw: the length of it is transverse, with a 
slight inclination backwards, and inwards, so that a line drawn, 

* Anat. Atlas, Figs. 48, 49, 
14* 



162 



SKELETON. 



through it would strike the foramen magnum occipitis. The an- 
terior margin of this cavity is formed by a tubercle, on which the 
condyle of the lower jaw rises when the mouth is widely opened. 
The outer margin of the glenoid cavity is formed by the root of 
the zygomatic process. The zygomatic process has a broad hori- 
zontal root, from which it extends outwardly, and then diminishing, 
runs forwards to join the malar bone. Posterior to the root of the 
zygomatic process, a small vertical groove may be seen occasion- 
ally, made by the middle temporal artery. 

The mastoid portion of the temporal bone, is thick and cellular. 
Its upper part forms an angle, which is received between the pa- 
rietal and occipital bones : both margins of this angle are serrated. 
Below, is the mastoid process, a large conical projection eight lines 
long, into which are inserted the sterno-mastoid, and trachelo-mas- 
toid muscles. At the inner side of its base is a fossa affording origin 
to the digastric muscle. The inner face of the mastoid portion is 
marked by a deep large fossa for the lateral sinus of the dura mater. 
In the posterior part of the suture, uniting the mastoid portion and 
the occipital bone, or in the former near the suture, is the mastoid 
foramen, for conducting a vein from the integuments into the lateral 
sinus. 

The cells in the mastoid portion are large and numerous, and ob- 
tain the name of sinuses ; they communicate with the tympanum by 
one large orifice. On the outer side of these sinuses a thin diploic 
structure is observable in some heads. 

The petrous portion of the temporal bone is a triangular pyramid; 
arising by a broad base from the inner side of the mastoid and squa- 
mous portions. It is fixed obliquely forwards, between the sphenoid 
and occipital bones. Its anterior surface is marked by the convolu- 
tions of the brain. Near the centre of this surface, and having a 
little superficial furrow leading to it, is a small foramen called the 
Hiatus Fallopii, through which passes the Vidian nerve. The pos- 
terior surface of the petrous portion presents a large foramen, the 
meatus auditorius internus, through which pass the seventh or the audi- 
tory and the facial nerve. Half an inch behind this orifice, is a very 
small one, overhung by a flat shelf of bone ; this is said to be the 
aqueduct of the vestibule. Just above the meatus auditorius internus. 



THE CRANIUM. 163 

is a foramen more patulous than the aqueduct, for transmitting small 
blood vessels. 

In the base of the petrous portion, between the mastoid and zygo- 
matic processes, is the meatus auditorius externus, a large opening 
conducting to the tympanum. It is oval, about half an inch deep, 
and varies much in its size in different subjects: its margin is called 
the auditory process, the lower part of which is very rough, for at- 
taching the cartilage of the external ear. 

The lower surface of the petrous bone is exceedingly irregular. 
Immediately below the meatus anditorius externus, is a depression 
which seems like a part of the glenoid cavity, and is improperly 
considered such by some anatomists, inasmuch as it does not form a 
portion of the articular surface for the lower jaw, but simply allows 
room for its motions, the parts which it contains (consisting of ves- 
sels, and a portion of the parotid gland) being pressed back when 
the jaw opens. Between this cavity and the glenoid is the glenoid 
dal fissure, separating the petrous from the squamous bone. In this 
fissure, leading to the tympanum, is a foramen which contains the 
processus gracilis of the malleus with its muscle, and the chorda 
tympani. The posterior margin of the depression just alluded to in 
the petrous bone, is made by a long rough ridge, called processus 
vaginalis; just behind which, and partially surrounded by it, is the 
styloid process. The styloid process is round, tapering, and an 
inch and a-half long; but frequently absent in prepared skulls, from 
accidental fracture and from being in a cartilaginous state. From, 
.it arise the styloid muscles. 

Behind the root of the styloid process, is the stylo mastoid fora- 
men, which transmits the portio dura or facial nerve to the face. 
Just within the styloid process and this foramen is a deep depres- 
sion, called jugular fossa, large enough to receive the tip of the little 
finger. The fossa, along with a corresponding one in the os occi- 
pitis, is occupied by the internal jugular vein and the eighth pair 
of nerves. Immediately before the lower end of this fossa is the 
foramen caroticum, being the lower orifice of a crooked canal, which 
terminates at the apex of the petrous bone, and transmits the carotid 
artery and the upper extremity of the sympathetic nerve. At the 
inner side of the carotid canal, a superficial serrated groove is per- 
ceived, which receives the adjoining edge of the occipital bone. 



164 



SKELETON. 



Just in advance of the inner part of the jugular fossa is a small 
spine of bone, at the foot of which is a pit, containing the orifice of 
the supposed aqueduct of the cochlea. The spine separates the 
eighth pair of nerves from the internal jugular vein. 

In the angle between the squamous and petrous parts, within the 
glenoid fissure, is the orifice of the Eustachian tube. The tube is 
divided longitudinally, by a bony partition. The upper division 
contains the tensor tympani muscle. 

A small groove exists along the superior angle of the petrous 
bone ; and another along the inferior angle, adjoining the basilar 
process of the occipital bone, and formed in part by it: they are 
made by the superior and the inferior petrous sinus. 

The temporal bone articulates with the occipital, the parietal, the 
sphenoid, and the malar. 



5. Sphenoid Bone, (Os Sphenoides, Sphenoide.*) 

The sphenoid is a symmetrica], but very irregular bone, placed 
transversely in the middle of the base of the cranium. 

It consists of a cuboidal body in the centre ; of a very large pro- 
cess called the great wing, spreading laterally to a considerable dis- 
tance on either side of the body; and it has, also, a number of 
angular margins and additional processes about it. 

In regard to the body of the sphenoid bone, from its upper ante- 
rior part arise, one on each side, the apophyses of Ingrassias, or the 
little wings. These wings have a broad horizontal base, and ex- 
tending themselves outwardly, terminate in a sharp point. Their 
anterior edge is serrated for articulating with the os frontis : the 
posterior edge is smooth. Between the two wings, in front, is a 
prominence united to the ethmoid bone. The base of the wing is 
perforated by the foramen opticum, for transmitting the optic nerve 
with the ophthalmic artery. Below and behind this foramen, the 
little wing terminates in a point, called the anterior clinoid process. 
Between the foramina optica is a ridge of bone, sometimes called 
processus olivaris, and just above the ridge a groove, made by the 
optic nerves where they unite. Behind the ridge is a depression, 
the Sella Turcica, for containing the pituitary gland. This depres- 

* Anat. Atlas, Figs. 50, 51. 



THE CRANIUM. 165 

sion is bounded behind by a very elevated transverse ridge, called 
the posterior clinoid process. At either extremity of the base of 
the latter, a groove (sulcus caroticus) is made by the carotid artery, 
which groove may be traced indistinctly under the anterior clinoid 
process, where it forms a notch, and sometimes a foramen. 

The posterior face of the body of the sphenoid bone, presents a 
flat surface for articulating with the cuneiform process of the occi- 
pital. In the adult, these bones are anchylosed at this junction. 
The inferior part of the body of the sphenoid presents a rising, in its 
middle, called the sphenoidal or azygous process, being for articula- 
tion with the vomer, and with the nasal septum of the ethmoid. On 
each side of this process, in front, is the orifice of the sphenoidal 
cells. These cells consist, most commonly, of one on each side, 
and are separated by a bony partition. In the very young bone 
they are not formed. The body of the sphenoid undergoes so many 
changes between early infancy and adult life, by the conversion of 
its diploic structure into sinuses or cells, and is also so much modi- 
fied in different individuals, that a general description of it will not 
answer for air specimens. 

The two great wings arise from the sides of the body of the sphe- 
noid, by a small irregular base. From their lower part project 
downwards, on either side, the two pterygoid processes called ex- 
ternal and internal. These processes have a common base, are 
partially separated behind by a groove called pterygoid fossa, and be- 
low by a notch. The internal is the longest, and is terminated by 
a hook, on the outer side of which is a trochlea made by the tendon 
of the Circumflexus Palati muscle. The external pterygoid process 
is the broadest. By applying together the temporal and sphenoid 
bones, a groove, common to the two, leading to the Eustachian 
tube, will be seen. This groove is continued obliquely across the 
root of the internal pterygoid process, and indicates the course and 
surface of attachment of the cartilaginous portion of the Eustachian 
tube. The internal pterygoid process sends out from its base a 
small shelf of bone, separated by a fissure from the under part of the 
body of the sphenoid. The posterior edge of the vomer rests against 
this projection. The fissure is filled up in advanced life. 

The great wings of the sphenoid bone present three faces. One 
is anterior, and called orb'tal, from its forming a part of the orbit ; 
another is external, and called temporal ; and the third is towards 
the brain, and forms a considerable part of the fossa for containing 



166 SKELETON. 

its middle lobe. The orbital face is square and slightly concave. 
The temporal face is an oblong concavity, at the lower part of which 
is a triangular process, giving an origin to the external pterygoid 
muscle. The cerebral face is concave and marked by the convolu- 
tions of the brain, as well as by a furrow made by the principal 
trunk of the great artery of the dura mater as it passes from the 
temporal bone to the temporal angle of the parietal. The inferior 
portion of the great wing is elongated backwards into a horizontal 
angle, called the spinous process, which is fixed between the petrous 
and squamous portions of the temporal bone. From the point of 
the spinous process projects downwards the styloid process. The 
great wing presents a triangular serrated surface above, at its outer 
end, by which it articulates with the os frontis ; just below this, in 
front, is a short serrated edge, by which it articulates with the 
malar bone ; and externally, is a semicircular serrated edge, by 
which it articulates with the squamous portion of the temporal 
bone. The tip of the large wing generally articulates also with the 
parietal bone, but in some cases the parietal does not come that 
far forward. 

Between the apophysis of Ingrassias and the greater wing is the 
foramen sphenoidale, called also foramen lacerum superius of the 
orbit. It is broad near the body of the bone, and becomes a mere 
slit at the extremity of the little wing. Through it pass the third, 
the fourth, the first branch of the fifth, and the sixth pair of nerves. 
Two lines below the base of this hole is the foramen rotundum, for 
transmitting the second branch of the fifth pair of nerves. Eight 
lines, or thereabouts, behind the foramen rotundum, is the foramen 
ovale, for transmitting the third branch of the fifth pair of nerves. 
Two lines behind the foramen ovale is the foramen spinale, for 
transmitting the middle artery of the dura mater. In the under 
part of the bone, and passing through the root of the pterygoid pro- 
cesses, is the foramen pterygoideum, for transmitting the pterygoid 
nerve ; it being a recurrent branch of the second branch of the fifth 
pair of nerves. 

The sphenoid* bone articulates above and in front with the vomer, 

* This bone is, by some anatomists, described in common with the os oc- 
cipitis, as the os basilare, in consequence of their early junction into a single 
piece. -i 



THE CRANIUM. 167 

the frontal, ethmoidal, malar, and parietal bones; laterally with the 
temporal, behind with the occipital, and by its pterygoid processes 
with the palate bones. 



6. Ethmoid Bone, ( Os Ethmoides, Ethmoide* J 

This bone is placed between the orbitar processes of the os frontis, 
and, as has been stated, fills the vacuity between them. It is cu- 
boidal, extremely cellular, and light. 

The horizontal portion between the orbitar processes is the cribri- 
form plate called so from its numerous perforations. This is divided, 
longitudinally, above and below, by a vertical process ; and from 
the under surface on each side, is suspended the cellular portion. 

The vertical process on the superior face of the cribriform plate 
is the crista galli, which extends sometimes from the back to the front 
of this plate, and is thickest in the middle. The commencement of 
the great falx arises from it, and occasionally it contains a cell or 
sinus opening into the nose. Between the front of the crista galli 
and the os frontis, is the foramen caecum, already described. On 
either side of the crista galli the cribriform plate is depressed into a 
gutter for holding the bulb of the olfactory nerve, and is perforated 
with many holes for transmitting its ramifications. The most ante- 
rior foramen on each side is oval, and transmits to the nose the in- 
ternal nasal nerve, after it has got into the cranium through the ante- 
rior internal orbitar foramen. The margins of the cribriform plate 
show many imperfect cells, which are completed by joining their 
congeners in the margins of the orbitar processes of the os frontis. 

The vertical process below the cribriform plate is called nasal 
lamella. It generally divides the nostrils equally, but is occasionally 
inclined to one side. It joins below, to the vomer and the cartila- 
ginous septum of the nose ; in front is in contact with the nasal spine 
of the frontal bone and with the nasal bones; and behind, with the 
azygous process of the sphenoid. 

Each cellular portion of the ethmoid forms, by its exterior, a part 
of the orbit of the eye, which surface is called os planum. The in- 

* Anat. Atlas, Fig. 52. 



168 



SKELETON - . 



ternal or nasal face forms part of the nostril. The fore part of this 
face is flat, but, posteriorly, in its middle, is a deep sulcus, called 
the superior meatus of the nose. The upper turbinated bone, a 
small scroll, constitutes the upper margin of this meatus. The in- 
ferior internal margin of the cellular portion of the ethmoid, is 
formed by another scroll of bone, running its -whole length. This 
is the middle turbinated bone. Moreover, from the inferior mar- 
gin of the cellular portion, one or more laminae, of an irregular form, 
project so as to diminish the opening into the upper maxillary sinus. 

The cells in the ethmoid bone are numerous and large, the pos- 
terior ones discharge, by one or more orifices, into the upper meatus. 
The anterior discharge into the middle meatus of the nose by seve- 
ral orifices, concealed by the middle turbinated bone. The most 
anterior of these cells is funnel-shaped, and joining the frontal sinus, 
conducts the discharge of the latter into the nose. 

In children of from three to eight years of age, there is attached 
to the posterior part of each cellular portion of the ethmoid, a tri- 
angular hollow pyramid, consisting of a single cell. This pyramid 
arises, not only from the cellular portion, but also from the posterior 
margin of the cribriform plate, and of the nasal lamella, by which 
it gains a large and secure base. The processus azygos of the sphe- 
noid bone is received between the two pyramids. In the base of 
the pyramid, communicating with the nose, is a foramen, which is 
known in adult life as the orifice of the sphenoidal sinus. The pyra- 
mid, towards puberty, becomes a part of the sphenoidal bone, and 
then detaches itself, by a suture at its base, from the ethmoidal. As 
life advances it is greatly developed, no indication of its original 
condition remains, and it becomes fairly the sphenoidal cell ; singu- 
larly differing in shape from what it was in the beginning.* 

Being put upon the investigation of this pyramid by the late pro- 
fessor Wistar, with the view of ascertaining its different phases of 
development, it has occurred to me to see it in every stage, from that 
of a simple triangular lamina, arising from the posterior margin of 
the cribriform plate, to the perfect hollow pyramidal state. The 
preceding anatomists describe it but imperfectly; it remained for 
that distinguished individual to elucidate its real history. 

* Wistar's Anatomy, vol. i. p. 31, 3d edit. 



THE FACE. 169 

Several of the articulations of the ethmoid have been mentioned ; 
the remainder will be introduced with the bones of the face. 



SECT. III. — OF THE FACE. 

The face being situated at the inferior anterior part of the base of 
the cranium, is bounded above by this cavity, laterally by the zygo- 
matic arches and fossae, and posteriorly by the space occupied by 
the pharynx. The best way of obtaining precise information con- 
cerning its form and composition, is from the head of a child, of 
from five to ten years, in which the bones can be easily parted. In 
the adult, somewhat advanced in life, the bones cannot be separated 
perfectly, from their being united more or less together by the 
obliteration of their -sutures. 

The face is composed of fourteen bones, thirteen of which enter 
into the upper jaw. Twelve of the thirteen are in pairs : they are 
the ossa maxillaria superiora, ossa malarum, ossa nasi, ossa ungues, 
ossa turbinata inferiora, ossa palati. The thirteenth is the vomer. 
A single bone, with corresponding or symmetrical sides, constitutes 
the maxilla inferior. 



1. Superior Maxillary Bones, (Ossa Maxillaria Superiora, Max- 
illaires Superieurs*) 

These may be known by their superior size, and by their com- 
posing almost the whole front of the upper jaw. They are too 
peculiar in their figures to admit of comparison with any common 
object. 

The superior face of these bones is formed by a thin triangular 
plate, the orbitar process, which is the floor of the orbit. In the 
posterior part of this plate is a groove, leading to a canal terminating 
in the front of the bone, at a foramen called infra-orbitar. This 
foramen is situated just below the middle of the lower margin of the 
orbit, and gives passage to the infra-orbitar nerve, and an artery. 
Externally, the orbitar plate is terminated by a rough surface, the 
malar process, which articulates with the malar bone. 

AnaU Atlas, Figs. 54, 55. 
Vol. I.— 15 



170 SKELETON. 

The nasal process arises, by a thick, strong root, from the front 
upper part of the bone at its inner side. Its front edge is thin, the 
posterior margin is thicker, and the upper edge is short, being ser- 
rated for articulating with the os frontis. A deficiency exists be- 
tween the orbitar process and the nasal process, for accommo- 
dating the os unguis, and the lachrymal sac. A groove, leading 
to the nose, is formed on the posterior face of the nasal process, 
and marks the situation and extent of the lachrymal sac. On that 
side of the root of the nasal process, next to the cavity of the 
nose, a small transverse ridge is seen, to which is attached the 
anterior part of the inferior turbinated bone. 

The under surface of the os maxillare superius is marked by 
the alveolar processes for lodging the teeth. These processes are 
broader behind than before, corresponding in that respect with the 
teeth. Within the circle of the alveoli is the palate process, 
arising from the internal face of the body of the bone. The palate 
process has a thick root, is thin in the middle, and, where it joins 
its fellow, has its margin turned upwards towards the nose into a 
spine or ridge, whereby its articular surface is increased. It pre- 
sents an oblong concave surface above, constituting the floor of 
the nostril; below, it, with its fellow, and the alveolar processes, 
form one concavity, having a surface somewhat rough, which is 
the roof of the mouth. The palate process does not extend the 
whole lenglh of the superior maxillary bone, but stops half an inch 
short of it, posteriorly, and with a serrated margin for the palate 
bone. When the two maxillary bones are in contact, we find in 
the suture, just behind the front alveolar processes, the foramen 
incisivum, which bifurcates, above, into each nostril. This fora- 
men contains a branch of the spheno-palatine nerve, and a gan- 
glion formed from it. 

In front, just below the infra orbitary foramen, the bone is de- 
pressed, which depression is filled up in the living state with fat 
and muscles. But, behind, the maxillary bone is elevated into a 
tuberosity, between which and the malar process is a broad 
groove, in which the temporal muscle plavs. 

The inner face of the upper maxillary bone presents a view of 
'he large cavity in the centre of it, called Antrum Highmorianum. 



THE FACE. 171 

The orifice by which this cavity communicates with the nose is 
much diminished by the palate bone behind, the ethmoid above, 
and the inferior spongy bone below. When the antrum is cut 
open a canal is seen on its posterior part, which conducts the 
nerve of the molar teeth to their roots, and a similar canal is seen 
in front of the antrum, for the nerves of the front teeth. The 
nerves, in both instances, come from the infra orbitary. The 
nerves, till they begin to divide into filaments, are between the 
lining membrane and the antrum, but afterwards they make com- 
plete canals in the alveolar processes. The antrum frequently com- 
municates with the frontal sinus, through the anterior ethmoidal 
cells, which circumstance is omitted by most anatomists. 

This bone is articulated with the frontal, nasal, unguiform, malar, 
and ethmoid, above ; to the palate bone behind ; to its fellow, and to 
the vomer, at its middle ; and to the inferior spongy bone by its nasal 
surface. 



2. Palate Bo7ies, (Ossa Palati, Palatins*) 

The palate bones, two in number, are placed at the back part of 
the superior maxillary, between them and the pterygoid processes of 
the sphenoid. 

For descriptive purposes they may be divided into three portions 
— the horizontal or palate plate, the vertical or nasal plate, and the 
orbitar or oblique plate, placed at the upper extremity of the latter. 

The palate plate is in the same line with the palate process of 
the superior maxillary bone, and supplies the deficiency caused by 
its abrupt termination. It is square. The inferior surface is flat, 
but rough for the attachment of the lining membrane of the mouth. 
The superior surface is concave, and forms about one-third of the 
bottom of the nose. The anterior margin is serrated where it articu- 
lates with the palate process of the maxillare superius. The posterior 
margin is thin and crescentic. The internal extremity of the crescent 
is elongated into a point, from which arises the azygos uvula? 
muscle. The internal margin of the palate plate is thick and ser- 

* Anat. Atlas, Fig. 56. 



172 SKELETON. 

rated for articulating with its fellow, the upper edge of it being turned 
upwards to join the vomer. The exterior edge touches the internal 
side of the maxillare superius, and from it arises the nasal plate. 

The nasal plate forms the posterior external part of the nostril, and is 
much thinner than the palate plate. Its side next the nose is slightly 
concave, and is divided into two unequal surfaces, of which the lower 
is the smaller, by a transverse ridge, that receives the posterior ex- 
tremity of the lower turbinated or spongy bone. The external face 
is in contact with the internal face of the maxillary bone, and presents 
a surface corresponding with it. The nasal plate of the palate bone 
diminishes the opening into the Antrum Highmorianum by overlap- 
ping it behind. Backwards it joins the pterygoid process of the 
sphenoid bone, and overlaps its anterior internal surface. 

At the inferior and posterior part of the nasal plate, where the 
crescentic edge of the palate plate joins it, the palate bone is ex- 
tended into a triangular process, called the pterygoid. This pro- 
cess, on its posterior surface, presents three grooves, the internal 
of which receives the internal pterygoid process of the sphenoid 
bone, and the external groove receives the external pterygoid pro- 
cess of the same bone. The middle fossa has its surface continuous 
with the pterygoid fossa of the sphenoid bone, and may be seen, in 
the articulated head, to contribute to this fossa. The anterior sur- 
face of the pterygoid process of the palate bone presents a small 
serrated tuberosity, which is received into a corresponding concavity 
on the posterior surface of the maxillary bone, and contributes to the 
firmer junction of the two. 

On the external surface of the nasal plate, between it and the 
base of the pterygoid process, a vertical groove is formed, which is 
converted into a complete canal by the maxillary bone. The lower 
orifice of this canal is near the posterior margin of the palate. It is 
called the posterior palatine foramen, and transmits the palatine 
nerve and artery to the soft palate. Immediately behind this canal 
there is, not unfrequently, a smaller one, running through the base 
of the pterygoid process of the palate bone, and transmitting a fila- 
ment of the same nerve to the palate. 

The upper extremity of the nasal plate is formed by two pro- 



THE FACE. 173 

cesses, one in front and the other behind, separated either by a 
round notch or a foramen. The posterior of the two, called also 
pterygoid apophysis, is inclined over towards the cavity of the nose. 
It is thin, and fits upon the under surface of the body of the sphe- 
noid bone, and upon the inner surface of the internal base of the 
pterygoid process of the same. Its upper edge touches the base of 
the vomer. The anterior process is the orbitar portion of the palate 
bone. 

The orbitar portion or plate is longer than the pterygoid apo- 
physis, and is hollow and very irregular. It may be seen in the 
posterior part of the orbit wedged in between the ethmoid and 
maxillary bone. The portion of it which is there seen, is the orbi- 
tal face, and is triangular. On the side of the ethmoid bone its 
cells are seen, which are completed by their contiguity to the eth- 
moid and sphenoid. The cells, in young subjects, are not always 
to be met with. The posterior face of the orbitar portion is wind- 
ing and looks towards the zygomatic fossa. 

The notch between the orbitar portion and the pterygoid apophy- 
sis is converted into a foramen, by that part of the body of the sphe- 
noid bone which is immediately below the opening of the sphenoid 
cell. Through this foramen, called spheno-palatine, pass the lateral 
nasal nerve, the spheno-palatine artery and vein. 

This bone can scarcely be studied advantageously except in the 
separated head. A single application of it to the maxillary, will 
then show how it extends from the palate of the mouth to the orbit 
of the eye ; and how it is the connecting bone between the maxil- 
lary bone and the pterygoid process of the sphenoid. 

The palate bone articulates with six others. With the upper 
maxillary, the sphenoid, the ethmoid, the inferior spongy, the vomer, 
and with its fellow. The places of junction have been pointed out 
in the description of the bone. 



15* 



174 



SKELETON. 



3. JVasal Bones, ( Ossa ./Va«, Os du JYez.*) 

The ossa nasi, two in number, fill up the vacancy between the 
nasal processes of the superior maxillary bones. They are oblong 
and of a dense compact structure, being so applied to each other 
as to form a strong arch called the bridge of the nose, which is 
farther sustained by the nasal spine and the contiguous oblique 
serrated surface of the os frontis. 

The ossa nasi are thick and serrated at their upper margins; 
below, they are thin and irregular. The surfaces by which they 
unite with each other are broad, comparatively smooth, with the 
exception of one or two small serrated processes, and have their 
edges raised where they join the nasal lamella of the ethmoid bone. 
The edge by which they join the nasal process of the upper max- 
illary bone is concave ; the upper part of this edge is overlapped 
by the nasal process, but the lower part of it overlaps the nasal pro- 
cess. There is a faint serrated arrangement also along this edge, to 
afford stronger adhesion to the nasal process. 

On the posterior face of the os nasi is to be seen a small longi- 
tudinal groove, formed by the internal nasal branch of the ophthal- 
mic nerve, which nerve penetrates the foramen orbitale anterius 
and the cribriform plate of the ethmoid bone. 

The ossa nasi articulate with each other in front, with the nasal 
processes of the upper maxillary, behind, with the septum nariura 
where they are in contact with one another, and with the os fion- 
tis above. 



4. Unguiform Bones, (Ossa Ungues, Os Lacrymaux.\) 

The unguiform is a very small thin bone, apt to be incompletely 
ossified, so that it puts on a cribriform condition; it is placed at 
the internal side of the orbit, between the nasal process of the upper 
maxillary and the os planum of the ethmoid. Its orbitar surface is 
divided into a face which is in a line with that of the os planum, 
and into an oblong vertical concavity, continuous with the conca- 
vity on the posterior surface of the nasal process, for lodging the 

* Anat. Atlas. Fig. 57. f Ibid, Fig. 58. 



THE FACE. 175 

lachrymal sac. Its inferior anterior coiner is elongated into the 
nose, so as to join with a process of the inferior turbinated bone, 
whereby the ductus ad nasum is rendered a complete bony canal. 

This bone lies on the orbitar side of the most anterior ethmoid 
cells, and completes them in that direction. 

An important variety in the structure of this part of the orbit 
occasionally occurs in which the whole fossa for lodging the lachry- 
mal sac, is formed by the unusual breadth of the nasal process of 
the upper maxillary bone. In this case, the only part of the os 
unguis which exists, is that in the same plane with the os planum. 
Several examples have come under my own notice. Duverney 
has also mentioned it. Sometimes the os unguis is entirely want- 
ing, in which case the os planum joins the nasal process.* A 
variety still more uncommon is mentioned by Verheyen, where the 
lachrymal fossa is formed exclusively by the os unguis. 

This bone articulates very loosely with the adjoining bones, so 
that it is frequently lost from the skeleton. It joins the os frontis 
above, the os maxillare superius before and below, the os planum 
behind, and the inferior spongy bone in the nose. 



5. Cheek Bones, (Ossa Malarum, Jugalia, Os de la Pommette*) 

These bones, two in number, are also called zygomatic by many 
anatomists. They are situated at the external part of the orbit of 
the eye, and form the middle external part of the face. 

The cheek bone is quadrangular, and has irregular margins. It 
consists of two compact tables with but little intermediate diploic 
structure. 

There are three surfaces to it. That which contributes to the 
orbit is crescentic, and is called the internal orbitar process. The 
exterior one is convex, and forms part of the face ; and behind it is 
a third surface, which is concave, and forms a part of the zygomatic 
fossa. Of the four margins, two are superior, and two inferior. 
The anterior of the first two is concave, and rounded off, to form 
the external and one-half of the lower edge of the orbit. The pos- 
terior upper border above, is thin and irregular, and to it is attached 

* Bertin, Traite D'Osteol. vol. ii. p. 143. Paris, 1754.. 
f Anat. Atlas, Fig. 60. 



176 



SKELETON. 



the temporal fascia : it terminates behind by a short serrated margin, 
for articulating with the zygomatic process of the temporal bone. 
The anterior inferior margin is serrated its whole length for arti- 
culating with its superior maxillary bone. The posterior infe- 
rior margin gives origin to part of the masseter muscle. Some 
anatomists admit, also, to this bone a fifth margin, which is towards 
the bottom of the orbit, part of which articulates above with the 
great wing of the sphenoid bone, and another part joins below with 
the superior maxillary. Between these two parts is a notch, forming 
the outer extremity of the spheno-maxillary slit. 

The angles of this bone are called processes. The upper one, 
which is continuous with the external angle of the os frontis, is the 
superior orbitar, or angular process. The orbitar margin termi- 
nates below, in the inferior orbitar, or angular process. That 
portion of the bone which joins with the zygoma of the temporal, 
is the zygomatic process; and the fourth angle is the maxillary 
process. 

The os malse articulates with four bones ; to wit, with the maxil- 
lary, frontal, sphenoidal, and temporal. 

There are some few small foramina in this bone, which transmit 
nerves and blood vessels. 



6. Inferior Spongy Bones, [Ossa Spongiosa aut Turbinata Inferiora y 
Cornets Inferieurs.*) 

This pair of bones is situated at the inferior lateral parts of the 
nose, just below the opening into the antrum Highmorianum. 
They are very thin and porous, and their substance is extremely 
light and spongy. 

The internal face of the spongy bone is towards the septum of 
the nose, and presents an oblong rough convexity. The external 
face has a corresponding concavity towards the maxillary bone. 
The superior margin presents, in front, an upright process, which 
joins with the anterior inferior angle of the unguiform bone, to 
form the nasal duct. Just behind this, the margin of the bone is 
turned over towards the antrum, forming a broad hook, which 
rests upon the lower margin of the orifice of the antrum, and 

* Anat. Alas, Fig. 59. 



THE FACE. 177 

diminishes its size. From the superior margin, also, one or two 
processes not unfrequently arise, whereby this bone joins the 
ethmoid. The inferior margin is somewhat thicker than the su- 
perior. 

The anterior extremity of this bone rests upon the ridge across 
the root of the nasal process of the upper maxillary. The poste- 
rior extremity rests, in like manner, upon the ridge across the 
nasal plate of the palate bone,* 



The Ploughshare , {Vomer.]) 

This single bone is placed between the nostrils, and forms a con- 
siderable part of their septum. It is frequently more inclined to one 
side than to the other. It is formed of two laminae, between which 
there is a very thin diploic structure. 

The sides of the vomer are smooth and parallel. It has four mar- 
gins. The superior is the broadest, and has a furrow in it for re- 
ceiving the azygous process of the sphenoid bone. The anterior 
margin being directed obliquely downwards and forwards, its front 
part joins the cartilaginous septum of the nose, and the posterior part 
receives, in a narrow groove, the nasal plate of the ethmoid. 

The posterior margin of the vomer is smooth and rounded, making 
the partition of the nostrils behind. The inferior margin articulates 
with the spine or ridge of the superior maxillary and palate bones, 
which exists at their internal border. 



Lower Jaw, (Os Maxillare Inferius, Maxillaire Inferieur.\) 

This bone forms the lower boundary of the face, and is the only 
one in the head capable of motion. In early life, its two halves are 
separable, being joined at the middle line only by cartilage ; but, in 
the course of two or three years after birth, they are consolidated, 
and the original cartilage disappears. 

It consists of a body or region which corresponds with the teeth, 
and two extremities or branches. 

* In some rare cases this bone adheres to the ethmoid, so as to become a 
part of it. 
| Anat. Atlas, Fig. 61. £ Ibid; Fig. 62. 



178 



SKELETON. 



The inferior part of the body presents a thick and rounded edge, 
which is the base. The upper part of the body is formed by the 
alveolar cavities for receiving the teeth. The line of union between 
the halves, being called the symphysis, is marked in front by an ele- 
vated ridge, terminated below by a triangular rising of the anterior 
mental tubercle. In many subjects this tubercle is bounded on each 
side by a rounded prominence of bone, which gives to the fore part 
of the jaw an unusual squareness in the living subject. Just above 
the latter prominence, there is, on each side, a transverse depression, 
from which arises the levator muscle of the lower lip. On a line 
with this depression, and removed a little distance from its external 
extremity, under the second bicuspate tooth or the interstice be- 
tween it and the first large molar tooth, is the anterior mental or 
maxillary foramen ; the termination of a large canal in either side of 
the bone, which conducts the inferior maxillary blood vessels and 
nerve to the teeth. The foramen is directed obliquely upwards and 
backwards, and transmits the remains of these blood vessels and the 
nerve to the face. The chin is that part of the bone between the an- 
terior mental foramina. As the alveolar processes do not exist in 
early life, and in very advanced age when the teeth are lost; the 
anterior mental foramen in such cases is very near the superior mar- 
gin of the bone. At it an obtuse ridge of bone commences, and 
which ends in the root or anterior edge of the coronoid process. 
The alveolar processes of the last three molar teeth are placed with- 
in this ridge, and project over the internal face of the bone. 

The internal or posterior face of the lower jaw is also marked at 
the symphysis by a ridge passing from the superior to the inferior 
margin. At the lower part of this ridge is a cleft process, the pos- 
terior mental tubercle. Below this tubercle, on either side, is a 
shallow fossa, for receiving the digastric muscle. Between the 
lower margin of the bone and the protuberance occasioned by the 
alveolar processes of the larger molar teeth, is an oblong large fossa, 
made by the pressure of the sub-maxillary gland. 

The alveolar processes form a semi-circle, the extremities of which 
are carried backwards with a slight divergence. The parietes of 
the processes are thin, and present cutting edges. They of course 
correspond, in number and shape, with the roots of the teeth which 
they have to accommodate. The anterior ones are deeper than the 
posterior. As a general rule, the alveolar processes may be said 



THE FACE. 179 

to come and depart with the teeth ; but, when a single tooth is ex- 
tracted, the alveolar cavity not unfrequently is filled up with osseous 
matter, the edge of it alone being removed. This occurs more fre- 
quently in the lower, than in the upper jaw. 

The base of the lower jaw does not present many marks worthy 
of attention. It should be observed, that its anterior part is thicker 
than the posterior; and that sometimes, just before the angle of the 
bone, we see a concavity of this edge, but generally it is straight, or 
nearly so. 

The extremities or rami of the lower jaw are quadrilateral, and 
rise up much above the level of the body. The superior margin 
presents a thin concave edge, bounded in front by the coronoid, 
and behind by the condyloid process. The coronoid process is tri- 
angular, and receives the insertion of the temporal muscle ; its base 
is thick, but its apex is a thin rounded point. The condyloid pro- 
cess is a transverse cylindrical ridge, directed inwards, with a slight 
inclination backwards, its middle being somewhat more elevated 
than the extremities. It springs from the ramus by a narrow neck. 
There is a concavity at the inner forepart of its neck for the inser- 
tion of the pterygoideus externus, and a convexity behind. 

The external face of the ramus is flat, but marked by the inser- 
tion of the masseter muscle. The internal face, at its lower part, 
is flat and rough, for the insertion of the pterygoideus internus. At 
the upper part of this roughness is the posterior mental or maxillary 
foramen, through which the inferior maxillary vessels and nerve 
pass. It is partially concealed by a spine of bone, into which a 
ligament from the os temporis is inserted. Leading from this fora- 
men is a small superficial groove, made by a filament of the inferior 
maxillary nerve. 

The angle of the inferior maxillary bone, formed by the meeting 
of the base and the posterior margin of the ramus, presents diver- 
sities well worth attention, at different epochs of life, and in diffe- 
rent individuals. In very early life, and in very advanced, when 
the alveoli are absorbed, it is remarkably obtuse. In most middle- 
aged individuals it is nearly rectangular. Besides which, its cor- 
ner is sometimes bent outwards and sometimes inwards, increasing 
or diminishing thereby the breadth of the face at its lower part. 

The substance of this bone, externally, is hard and compact. 
Internally there is a cellular structure, through the centre of which 



180 



SKELETON. 



runs the canal for the nerves and blood vessels. From this canal 
smaller ones are detached, containing the vascular and nervous fila- 
ments which go to the roots of the teeth. The condyles or condy- 
loid processes of the os maxillare inferius articulate with the tempo- 
ral bones, by means of their glenoid cavities. 

. Remarks. — The os maxillare inferius has a greater influence on the 
form of the face than any other bone entering into its composition. 
Sometimes it is much smaller in proportion in certain individuals 
than in others. Sometimes its sides, being widely separated, 
cause a great shortening to the chin, and breadth to the lower hind 
part of the face. In many instances, the alveolar processes, in front, 
incline obliquely over the outer circumference of the bone, and 
thereby give to the chin the appearance of receding considerably. 
In others, the alveoli incline over the inner circumference, which 
causes the chin to project unusually. 



CHAPTER III. 

General Considerations on the Head. 

Having described the individual bones of the head, it will now 
be proper to consider it as a whole. 

SECT. I. — OF THE SUTURES.* 

Except in advanced age, the bones of the cranium and of the 
face are very distinctly marked off and united by sutures. 

The latter are formed by the proximate edges of the contiguous 
bones, presenting a multitude of sharp serrated points, and of deep 
narrow pits, by which they interlock by an accurate and firm con- 
tact. Here and there, in the sutures which unite the flat bones of 
the cranium, we find not only sharp points, but complete dovetail 

Anat. Atlas, Figs. 63, 64. 



THE SUTURES. 181 

processes of the one bone received into corresponding cavities of 
the other. The denticulation of the sutures is much more common, 
and much better marked, on the external than on the internal surface 
of the cranium. On the latter, the union of the bones is, in several 
instances, by a joint nearly straight; in which case, the denticula- 
tion is almost exclusively confined to the external table and to the 
diploic structure. 

The Coronal Suture, (Sutura Coro?ialis,) so named from its cor- 
responding in situation with the garlands worn by the ancients ; 
begins at the sphenoid bone, about an inch and a quarter behind 
the external angular process of the os frontis. It inclines so much 
backwards in its ascent, that when we stand erect, with the head 
in its easiest position, a vertical line, dropped from its point of 
union with the sagittal suture, would pass through the centre of the 
base of the cranium, and would cut another line drawn from one 
meatus auditorius externus to the other. It unites the frontal bone 
to the two parietal. 

The Sagittal Suture (Sutura Sagittalis) unites the upper margins 
of the two parietal bones, and is immediately over the division be- 
tween the hemispheres of the cerebrum. It has been stated in the 
account of the os frontis, that sometimes it is continued through the 
middle of this bone down to the root of the nose. 

The Lambdoidal Suture (Sutura Lambdaformis) is named from 
its resemblance to the Greek letter lambda, and consists of two long 
legs united angularly. It begins at the posterior termination of the 
sagittal suture, and continues down to the base of the cranium, as 
far as the jugular eminences of the occipital bone. Its upper half 
unites the occipital to the parietal bones, and the lower half the oc- 
cipital to the temporal bones. The latter half is sometimes called 
the Additamentum Suturae Lambdoidis. 

The Squamous Suture (Sutura Squamosa) is placed on the side of 
the head, and unites the parietal to the temporal bone. The convex 
semi-circular edge of the latter overlaps the concave edge of the 
former. The squamous suture is converted into the common ser- 
rated one, where the upper edge of the angle of the temporal bone 

Vol. I.— 16 



182 



SKELETON, 



joins the parietal. This portion is called the Additamentum Suturae 
Squamosa?. 

The squamous mode of suture unites, likewise, the great wing of 
the sphenoidal to the temporal angle of the parietal. 

In the upper part of the lambdoidal suture, particularly, we find 
in many skulls one or more small bones, connected to the parietal 
and occipital bones by serrated margins. They are called the Ossa 
Wormiana or Triquetra. They vary very much in their magnitude, 
being in different subjects from a line to one inch, or an inch and 
a-half in diameter. I have seen them of the latter size, and even 
larger, occupying entirely the place of the superior angle of the os oc- 
cipitis. Most commonly, but not always, when one of these bones 
exists on one side of the body, a corresponding one exists on 
the other. A congeries of these bones, united, successively, is 
sometimes found in the lambdoidal suture ; in such cases they are, 
for the most part, small. Commonly these bones consist, like the 
other bones of the cranium, of two tables and an intermediate diploe, 
and form an integral portion of the thickness of the cranium ; some- 
times, however, they compose only the external table. M . Bertin 
says, that he has seen them, also, composing only the internal table 
of the cranium. 

All the sutures mentioned besides the lambdoid, may exhibit, at 
any of their points, the Ossa Triquetra or Wormiana. We have 
examples of them in the coronal, the sagittal, and the squamous, 
but in such cases they are small. The lambdoid unquestionably has 
them most frequently. M. Bertin has seen a large square bone at 
the fore part of the sagittal suture, occupying the place, and present- 
ing the form, of what was once the anterior fontanel : he has also 
seen triquetral bones in the articulations of the bones of the face.* 

The sutures described belong exclusively to the cranium, but 
there are others common to it and to the face. The sphenoidal suture 
surrounds the bone from which its name comes ; the ethmoidal suture 
surrounds the ethmoidal bone ; the zygomatic suture unites the tem- 
poral and malar bones ; the transverse suture runs across the root of 
the nose, and also unites the malar bones to the os frontis. The 
other articular lines of the face derive their names from the bones 

* Bertin, Traite D'osteoL 



THE SUTURES. 183 

they unite, and do not merit a particular attention at this time, as 
enough has been said in the description of the bones themselves. 

The base of the cranium is remarkably different, in the manner 
of its articulations, from the upper part. The surface, in the first 
place, is very rugged, and much diversified by its connexion with 
muscles and bones : besides which, there is a considerable number 
of large foramina and fissures in it for the blood vessels and nerves. 
To guard against the weakness arising from the latter arrangement, 
nature has given a very increased thickness to the base, particularly 
where much pressure from the weight of the head exists, and has 
applied unusually broad surfaces of bone to each other to secure 
them from displacement by concussion, and different kinds of vio- 
lence. These arrangements are particularly manifest at the junc- 
tion of the cuneiform process of the occipital bone with the body of 
the sphenoid, which, in middle age or rather shortly after puberty is 
anchylosed ; — at the lower part of the lambdoidal suture ; — and at the 
margins of the petrous portion of the temporal bones where they 
touch the contiguous bones. Whence it results that the several 
fastenings of the base of the cranium, and also of the upper maxilla, 
are so complete and strong, that they are most generally perfectly 
exempt from dislocation ; and when the violence offered to them is 
sufficiently great, the bones, in place thereof, are fractured. 

The use of the sutures, in the cranium and upper maxilla, is 
somewhat problematical; for as none of the bones move, the head 
might have been equally well arranged by being made of a single 
piece. In proof of which it is only necessary to recollect, that in 
the very aged there is frequently not a bone of the cranium and 
upper maxilla to be found in an insulated state: they are all blended 
with the adjoining bones, by the obliteration of their sutures. The 
old notion that sutures existed for the purpose of arresting the course 
of fractures, and for opening in some diseased conditions of the 
brain, has been very justly exploded. We know that a fracture 
will traverse a suture readily, and that the opening of the sutures 
from hydrocephalus is an occurrence only of very early infancy, 
where the sutures have not arrived at the serrated and dove-tail 
arrangement, by which they are subsequently secured. It is much 
more probable that the true ground for the existence of sutures, is 
found among the laws peculiar to the growing state ; and which 
most commonly are suspended after the several developments have 



184 



SKELETON. 



been accomplished. Thus, the head, in consequence of being 
separated by sutures into many pieces, is more readily wrought from 
its form and size in the embryo state, to the form and size required 
by adult life. This necessity of subdivision into many pieces, does 
not depend so much on the size, as on the shape of the head. For 
we find the largest animal, as the elephant, having no more sutures 
than the smallest, as the mouse. This opinion is also sustained by 
what we see in other bones. Bones of a very simple shape, as 
those of the tarsus and carpus, consist from the very beginning of 
buf one piece. But where the shape of a bone is complicated, we 
find it, while growing, submitted to the same law as the head at 
large, and consisting of many pieces. In such cases these pieces 
are united by a species of suture corresponding precisely with the 
form of suture observed between some of the bones of the cranium; 
as, for example, between the occipital and the sphenoid. Thus, 
the os femoris, till adult age, consists of five pieces: its two articular 
extremities, its body, its trochanter major, and its trochanter minor. 
The cranium itself, before birth, and for some time after, has several 
of its individual bones consisting each of two, or more pieces, which 
favours still more the idea. 

Some persons think that the sutures of the adult are only remains 
of an arrangement intended exclusively for the benefit of the par- 
turient state, by maintaining a plasticity of the head of the foetus, 
which admits of its diameters accommodating themselves to the 
diameters of the pelvis of the mother. This theory is rather too 
exclusive, though it may be admitted that the sutures in a foetal 
head have that use, and are in some cases of parturition a most 
fortunate coincidence, by which the lives of both parties are saved. 
But it should be observed that in a great number of cases, the head 
of the foetus never changes its form in passing through the pelvis, 
because the passage is quite large enough without it; and, again, 
if the sutures were intended expressly for the parturient state, we 
ought not to find them in birds, and in such animals as are hatched, 
because the necessity for them there does not exist.* 

Upon the whole we may safely conclude, that the sutures of the 
cranium and face are simply a provision for the growing state, and 
that, like all other provisions for this state, it also ceases at its ap- 

* A gentleman whose anatomical writings have some vogue in this country, 
nas cut the Gordian knot, by telling us that they are " accidental merely, and 
of little use .'.'" — Anat. of the Human Body, by John Bell, Surgeon, Edinburgh. 



THE SUTURES. 185 

propriate period, and sometimes leaves not a vestige of its existence. 
Occasionally, indeed, we find the latter to have occurred in one or 
more sutures, even before the age of puberty, as I have repeatedly 
witnessed in the sagittal, the squamous, and the larnbdoidal sutures. 

The manner in which the sutures are formed is sufficiently inter 
resting: they are generally said to be made by the radii of ossifica- 
tion, from the opposite bones meeting and passing each other, so as 
to form a serrated edge. This explanation may account partially 
for the shape of the edge of the sutures, but not for their uniform 
position; inasmuch as we nearly always find the sutures in the same 
relative situation, and having the same course. If they depended 
exclusively on so mechanical a process, as the rays of one bone 
shooting across the rays of another by their own force, we ought to 
see, more frequently, the sagittal suture more on one side of the 
head than on the other, and not straight, because in some instances 
ossification is a more rapid process on one side than on the other. 
Moreover, in all cases where bones arise from different points of 
ossification, and meet, the serrated edge should be formed; and 
particularly in the flat bones. Observation, however, proves that 
the os occipitis, which is formed originally from four points of ossi- 
fication, and therefore has as many bones composing it in early life, 
does not present these bones afterwards united by the serrated edge. 
The acromion process of the scapula, though originally distinct 
from the spinous, never unites to it by suture, but always by fusion- 
The mode of junction in the three bones of the sternum is always 
by fusion. In short, the observation holds good in numerous other 
instances. 

Bertin and Bichat, reject fully the mechanical doctrine concerning 
the sutures, and present one founded upon reason and observation, 
and susceptible of confirmation by any accurate observer. The dura 
mater and the pericranium, before ossification commences, form one 
membrane consisting of two laminae. Partitions pass from one of 
these laminae to the other, which mark off the shape, or constitute 
the mould of the bones long before they are perfected. The peculiar 
shape of the bony junction, or, in other words, of the sutures or edges 
of the bones in adult life, depends, therefore, exclusively upon the 
original shape of the partitions. When the latter are serrated, the 
points of ossification will fill up these serrse; but when they are 
oblique, the squamous suture will be subsequently formed. 

16* 



186 



SKELETON. 



This theory also accounts for modes of junction intermediate to 
the squamous and serrated suture; for the formation of the Ossa 
Triquetra or Wormiana; for their existence, form, size, and number, 
in some skulls, and their total absence in others. The inference 
will also be obvious, that in all ossifications from different nuclei, a 
suture will not be formed, where the membranous partitions do not 
exist ; but that the bones will unite after the manner of such as are 
fractured. We shall also understand, that when these partitions are 
weak and imperfect, either from their congenital condition, or from 
advanced age, as happens in all sutures, but with some differences 
of time, the bones of the opposite sides are blended together com- 
pletely. 

The partitions which determine the places of the sutures, may be 
demonstrated in a young adult skull by removing with muriatic acid 
the calcarious portion of the bones, so as to leave only the animal 
part. On opening the suture after this process, it will be seen, that 
the pericranium sends in its partition, which is met by the partition 
coming from the dura mater. Or, if either of these membranes be 
peeled off, its contribution of partition will appear very plainly pro- 
jecting from its surface, in the form of a ridge. 

Owing to congenital hydrocephalus, the sutures of the vault of the 
cranium have been known to remain open for years after birth, from 
the continued augmentation of the volume of the brain. In such 
cases additional bones are sometimes formed, manifesting a strong 
attempt, on the part of nature, to cover the brain with bone. I 
obtained, several years ago, a specimen of this kind belonging to a 
foetus of nine months, whose head was as large as it is commonly in 
adult life, and in whom there were two ossa parietalia on one side. 
Morgagni,* whose authority is proverbial in morbid anatomy, states, 
that a learned colleague and intimate friend of his, Bernardin Ram- 
mazzini, aged seventy, had the sutures open at that period of life. 
He does not say at what time this condition of them appeared. I 
think it more probable that they had never been closed, though 
Morgagni leaves the reader to infer, that it was a circumstance 
which had arisen from a violent hemicrania, with which the patient 
had been seized when he was advanced in life. Diemerbroeck 
found, in a woman of forty, the anterior fontanel not ossified. Bau- 

* Causes and Seats of Disease, Letter 3d, Art. 8th. 



STRUCTURE OF THE CRANIUM. 187 

hius' wife, aged twenty-six, had the sutures not yet closed. Indeed, 
there is no deficiency of well authenticated similar instances, more 
of which it will be unnecessary to adduce. It may be observed 
here, that when from congenital hydrocephalus, attended with much 
extension of the brain, the bones of the cranium are compelled to 
grow beyond their usual diameters, they are uncommonly thin, and 
the diploic structure is very imperfectly developed : which will ac- 
count for their separation at any period of life, from the fastening 
being so slight. 



SECT. II. OF THE DIPLOIC STRUCTURE OF THE CRANIUM.* 

The bones of the cranium, in the adult, consist of an external and 
of an internal table ; united by a bony reticulated or cellular sub- 
stance, which does not manifest itself very distinctly till two, three, 
or even more years are passed, by the infant. The internal table of 
the skull is thinner and more brittle than the external, and has ob- 
tained, from that cause, the name of vitreous table. 

The cells of the diploic structure are not to be confounded with 
the large sinuses described, that exist in the frontal, the temporal, 
and the sphenoidal bones. They are formed under different cir- 
cumstances, and do not communicate with them. The sinuses are 
lined by a mucous membrane, whereas the lining membrane of the 
cells of the diploe corresponds with the internal periosteum of other 
bones. I have a preparation, in which a diploic structure of the os 
frontis exists between its sinuses and the external table of the bone : 
in the same head, a similar circumstance existed in regard to the 
poralbone; from which we infer that the diploic structure, in 
these places, is caused to recede, and even to be partially obliterated, 
when the development of the sinus commences,- which is not until 
some time after the evolution of the diploic structure. The sphe- 
noidal bone, when fully evolved in its body, is a remarkable in- 
stance of the recession of diploic structure for the purpose of form- 
ing a sinus. 

In the diploe of the dried- bones, several arborescent channels! 
may be seen by the removal of the external table. They were dis- 

* Anat. Atlas, Fig. 65. 

■[ Chaussier, Exposition de la Structure de l'Encephale. Paris, 1807.. 



188 SKELETON. 

covered about the year 1805, by M. Fleury, while he was Prosec- 
tor at the School of Medicine in Paris: and engaged, at the insti- 
gation of the venerable Chaussier, in some inquiries relative to the 
structure of the cranium. The account given by the latter is, that 
these channels are occupied in the recent subject, by veins, which, 
like all others, are intended to return the blood to the heart. These 
veins are furnished with small valves, have extremely thin and deli- 
cate parietes, and commence by capillary ramifications, coming from 
the different points of the vascular membrane, which lines the cells 
of the diploe. Their roots are at first extremely fine and nume- 
rous, form by their frequent anastomoses a kind of net- work, 
and produce by their successive junction, ramuscles, branches, 
and large trunks, which, becoming still more voluminous, are 
directed towards the base of the cranium. Some variations exist 
in regard to the number, size, and disposition of these trunks ; 
but generally one or two of them are found on either side of the 
frontal bone, two in the parietal bone, and one on either side of the 
occipital bone. Anastomoses exist between these several trunks, by 
which the veins in the parietal bone are joined to those in the frontal 
and in the occipital. Branches from the right side of the head also 
anastomose with some from the left side. Besides the branches al- 
ready mentioned, one or two smaller than the others are directed 
towards the top of the head, and terminate in the longitudinal sinus. 

The descending veins of the diploe communicate in their passage 
with the contiguous superficial veins, and empty into them the blood 
which they receive from the several points of the diploe. These 
communications are passed through small foramina, which penetrate 
from the surface of the bone to the diploe. The trunks of such 
diploic veins as are continued to the base of the cranium, open 
partly into the sinuses of the dura mater, and partly into the venous 
plexus at the base of the pterygoid apophyses of the sphenoid bone, 
and form there the venous communications through the foramina of 
the base of the cranium, called the emissaries of Santorini. More- 
over, there are communications sent from the diploic veins, through 
the porosities of the internal table of the skull, to the veins of the 
dura mater. This fact is rendered very evident by tearing off the 
skull-cap, when the surface of the dura mater will be studded with 
dots of blood, 'and the internal face of the bone also, particularly in 
apoplectic subjects. It appears, indeed, that the arteries of the era- 



SURFACE OF THE CRANIUM. 189 

nium are principally distributed on its external surface, and the 
veins on its internal surface and diploe. 

In the infant, the diploic veins are small, straight, and have but 
few branches : in the adult, they correspond with the description 
just given, and, in old age, they are still more considerable, forming 
nodes and seeming varicose. In children, when the bones are dis- 
eased, they partake of the latter character. In order to see them 
fully, the external table of the skull must be removed, both from its 
vault and base, with a chisel and mallet. This operation will be 
much facilitated by soaking the head previously in water for two 
days. 

The diploic sinuses as well as the corresponding channels in the 
bodies of the vertebra? are now considered as an enlarged develop- 
ment of Haversian canals. 



SECT. III. — THE INTERNAL SURFACE OF THE CRANIUM. 

The points for study in viewing the cranium as a whole, are 
generally the same as have been presented in the detail of each 
bone. It is, nevertheless, useful to regard the structure in its con- 
nected state, as new views are thus presented of the relative situa- 
tion of parts, and of the formation of the several fossae and cavi- 
ties. 

The cavity for containing the brain is regularly concave above, 
and is there called the arch or vault ; but below, it is divided into 
several fossse, and is called the base. 

The whole cavity is lined by the dura mater, and, in the adult, 
presents round superficial depressions made by the convolutions of 
the brain. These depressions are seldom deep enough to prevent 
the internal periphery of the vault and sides of the cranium, from 
being nearly parallel with their external surface. 

On the Vault, or arch, are to be seen, on the middle line, the 
frontal spine, extending from the ethmoid bone half way or more 
up the os frontis: also, the gutter for the longitudinal sinus leading 
from this spine along the sagittal suture, and terminating at the 
internal occipital protuberance. On either side of this gutter are 
the arborescent channels, made by the great middle artery of the 
dura mater. In this section, we also see the internal face of the os 



190 SKELETON. 

frontis, excepting its orbitar processes ; the parietal bones ; and the 
superior fossae in the occipital bone, for the posterior lobes of the 
cerebrum. 

The Base of the cranium internally presents a very unequal sur- 
face, abounding in deep depressions, process, and foramina.* On 
its middle line, extending from before backwards, the following ob- 
jects should be remarked. The foramen ccecum at the front of the 
crista galli ; and, at either side of the latter, the ethmoidal gutter, 
perforated with holes. These gutters are bounded, laterally, by 
the internal margin of the orbitar processes of the os frontis, and 
behind by the sphenoid bone. At the fore part of the gutter is the 
oblong foramen for transmitting to the nose the internal nasal nerve, 
and about half an inch behind this foramen, in the suture, with the 
os frontis, is the inner orifice of the foramen, called the anterior in- 
ternal orbitar, which leads the same nerve from the orbit. Imme- 
diately behind the ethmoidal fossae the sphenoid bone presents a 
plain surface, upon which are placed the olfactory nerves and the 
contiguous part of the brain. Behind this plane is the fossa, run- 
ning from one optic foramen to the other, for lodging the optic 
nerves. Behind this, again, is the sella turcica or pituitary fossa, 
bounded at its two anterior angles by the anterior clinoid processes, 
and behind by the posterior clinoid process. Posterior to the latter 
is a plain square surface of the sphenoid bone, continuous with the 
internal surface of the cuneiform process of the os occipitis. On 
the latter is the depression called basilar gutter, for receiving the 
Pons Varolii; also the medulla oblongata, and which is bounded 
below by the great occipital foramen. From this foramen to the 
internal occipital protuberance, proceeds the inferior limb of the oc- 
cipital cross. 

On both sides of the ethmoidal bone is a convex surface ; called, 
however, the anterior fossoe of the base of the cranium, and formed 
by the orbitar processes of the os frontis and the little wings of the 
sphenoid bone, for lodging the anterior lobes of the cerebrum. 
This surface is terminated behind by the rounded edge of die little 
wing, which is received into the fissure between the anterior and 

* Anat. Atlas, Fig. 66. 



SURFACE OF THE CRANIUM. 191 

middle lobes of the brain. Just anterior to this edge is the fronto- 
sphenoidal suture. 

On the sides of the sella turcica are the middle fossae of the base 
of the cranium for lodging the middle lobes of the cerebrum. They 
are very wide externally, where they are bounded by the squamous 
portions of the temporal bones, but narrow internally, where they 
are bounded by the Sella Turcica. The little wings of the sphe- 
noidal bone terminate them in front, and form there a crescentic 
edge hanging over their cavity. Their posterior margin is the su- 
perior ridge of the petrous bone. This bone is placed very obliquely, 
inwards and forwards, and at its point almost reaches the posterior 
clinoid process. At the anterior part of the fossa is the sphenoidal 
fissure or foramen, of the sphenoidal bone. Just above the base of 
this fissure is the foramen opticum, partially concealed by the ante- 
rior clinoid process. Just below the base of the fissure is the fora- 
men rotundum. At the point of the petrous bone, by the side of 
the posterior clinoid process, is the internal orifice of the carotid 
canal. On a line with the latter, exteriorly, is the foramen ovale. 
Two lines behind the latter is the foramen spinale. The groove 
formed by the middle artery of the dura mater, may be traced from 
the foramen spinale along the anterior margin of the squamous bone. 
Near the upper part of this bone the groove bifurcates ; the larger 
channel runs upwards into a groove on the tip of the great sphe- 
noidal wing, into the principal groove of the parietal bone, which 
commences at the temporal angle of the latter. The smaller groove 
runs horizontally backwards, and just above the base of the petrous 
bone is continued also in the parietal bone. On the front of the 
petrous portion may be seen the hiatus Fallopii. The sphenoidal 
suture runs through these fossse, in the examination of which, the 
reception of the spinous process of the sphenoid bone, between the 
squamous and petrous portions of the temporal, will be readily 
understood. 

On each side of the foramen magnum occipitis are the two posterior 
fossoe of the base of the cranium, formed by the posterior faces of the 
petrous bones, the angles of the mastoid portions of the temporal 
bones and by that surface of the occipital bone below T its horizontal 
ridges. These two fossse are very partially separated by the inferior 
ridge of the occipital cross and receive the hemispheres of the cere- 



192 SKELETON. 

bellum. The additament of the lambdoidal suture traverses these 
fossae. At the junction between the petrous bone and the basilar 
process of the occipital, in the course of the suture, is a groove for 
the inferior petrous sinus. The groove conducts to the posterior 
foramen lacerum, which has a small part separated from it by the 
little spine of the petrous bone, which, with the assistance of the 
dura mater, forms a distinct foramen for the eighth pair of nerves. 
The posterior foramen lacerum being common to the temporal and 
occipital bones, is occasionally much larger on the right than 
on the left side: in which case, the groove that leads from 
it along the angle of the temporal bone, the inferior corner of the 
parietal, and the horizontal limb of the occipital cross, is also larger. 
Above the foramen lacerum are the meatus auditorius internus, and 
the internal orifice of the aqueduct of the vestibule. Between the 
foramen lacerum and foramen magnum occipitis is the anterior con- 
dyloid foramen. The two posterior fossae of the base of the cranium 
contain the cerebellum. 



SECT. IV. — OF THE EXTERNAL SURFACE OF THE HEAD. 

Anatomists consider the external surface of the head as forming 
or representing three ovals and two triangles, each of which con- 
stitutes a region. The first oval is the whole superior convex part 
of the cranium ; or, in other words, the external surface of its vault. 
The second oval is formed by the inferior surface of the cranium, 
and of the face. The third oval is formed by the lower front part of 
the os frontis, and by the face. Each side of the head forms one of the 
triangular regions. 

The superior region is so simple, and its parts have been so closely 
sketched, that it is unnecessary to repeat the description. 

The inferior region or oval, extends from the chin to the occipital 
protuberance, and is bounded in its transverse diameter by the su- 
perior semi-circular ridges of the os occipitis, by the mastoid pro- 
cesses, and by the rami and base of the lower jaw. This surface is 
subdivided into Palatine, Guttural, and Occipital sections or re- 
gions.* 

The Palatine region or section, is formed by the superior max- 

* Anat. Atlas, Fig. 67. 



SURFACE OF THE HEAD. 193 

illary and palate bones, above, and by the inferior maxillary bone, 
laterally and below. It is a deep fossa, the circumference of which 
is represented by the letter U, the open part being behind. The 
whole upper surface of the palatine region, presents a number of 
small rough elevations and fossae, for the attachment of the lining 
membrane of the mouth. The surface is divided into two equal 
parts by the long or middle palate suture, which is crossed at its 
posterior part by the transverse palate suture. The posterior margin 
of the hard palate is concave on each side of the mouth ; and from 
it is suspended the soft palate. The point in the centre of this mar- 
gin gives origin to the azygos uvulae muscle. 

The foramina on this surface, are the anterior palatine or foramen 
incisivum, in the long palate suture just behind the incisor teeth, 
and on either side, behind, between the palate and pterygoid pro- 
cess of the palate bone, bounded exteriorly by the upper maxillary, 
is the posterior palatine foramen. About one or two lines behind 
this, is another foramen, in the base of the pterygoid process of the 
palate bone, through which pass fibrillae, of the same nerve that oc- 
cupies the posterior palatine foramen. The posterior palatine fora- 
men also transmits an artery to the soft palate, the mark of whose 
course may be seen at the base of the alveolar processes for the 
molar teeth. 

The internal surface of the lower jaw has been sufficiently described 
in the account of that bone. 

The depth of the palatine fossa depends on the state of the teeth. 
When they are removed by old age, and the alveolar processes also, 
what was palatine fossa of the upper maxilla is almost a plain sur* 
face : and in many instances of extreme old age, the palatine fossa is 
wholly obliterated, excepting the part formed by the remains of the 
lower jaw. The separation from the nose is also extremely thin, 
and not unfrequently imperfect. The transverse diameter of the 
mouth is much decreased, in consequence of the absorption of the 
alveolar processes taking place, from the outside towards the inside. 

The Guttural Region of the base of the head is formed by the 
cuneiform process of the os occipitis, in the centre ; by the inferior 
face of the petrous bones, laterally and behind; by the body and 
great wing of the sphenoid bone, laterally and in front ; and by the 
several bones contributing to the orifice of the posterior nares. 

It is bounded anteriorly by the pterygoid fossa? and the openings 
of the nose, and behind by the mastoid processes and by the con- 1 ' 

Vol, I.— 17 



194 



SKELETON. 



dyles of the os occipitis. It consists, consequently, in one part, 
which is horizontal, and in another, which is vertical. In regard to 
the horizontal portion, its inequalities, processes, and fossae, have been 
already stated. The relative position of its foramina, cannot, how- 
ever, be studied except in the united bone. The following rules 
will afford some assistance in determining their position, even on the 
living body. 

A line passing from the anterior margin near the end of one mas- 
toid process to the corresponding point of the other, will subtend 
the stylo-mastoid foramina, and the posterior margin of the foramina 
lacera ; it will also touch the base of the styloid processes, and cut 
into halves the condyles of the occiput. A line, three-eighths of an 
inch in advance of this, run through the middle of the meatus audi- 
torius externus, will indicate the posterior margins of the glenoid 
cavities,* and cut in half the inferior end of the carotid canals or 
foramina, and touch the anterior margins of the anterior condyloid 
foramina. Another line, one fourth of an inch in advance of the 
latter, will cut through the centre of the glenoid cavity, and subtend 
the styloid process of the sphenoid bone, and the bony orifice of the 
Eustachian tube in the temporal bone. A line passing between the 
external ends of the tubercles of the temporal bones, will subtend 
the foramina ovalia and the foramina lacera anteriora. The foramen 
spinale is about equi-distant from the last two lines. 

The* foramen lacerum anterius, being at the point of the petrous 
bone, is occasioned by the latter not filling up the space between it 
and the sphenoidal and occipital bones. The deficiency is supplied, 
in the recent state, by cartilage. Precisely opposite to the point of 
the petrous bone, is the posterior orifice of the foramen pterygoideum, 
from which emerges the pterygoid nerve, and penetrating this car- 
tilage immediately divides into two branches : that going to the carotid 
canal, becomes one of the roots of the sympathetic nerve ; and the 
other, ascending into the cranium, becomes the Vidian nerve or 
superficial petrous. 

The vertical portion of the Guttural Region presents the posterior 
orifices of the nostrils, separated from each other by the vomer. On 
each side are the pterygoid processes of the sphenoid bone, and 

* By glenoid cavity in this paragraph is meant the whole of the depression 
in the temporal bone, and not merely the surface for the condyle of the lowef 

jaw. 



SURFACE OF THE HEAD. 195 

above is its body. The pterygoid fossa, formed between the ex- 
ternal and internal process, and the long unciform termination of 
the latter with the broader and shorter termination of the former, 
will also be observed. 

The Occipital region of the base of the head, placed immediately 
behind the other, may be considered to include the mastoid pro- 
cesses, and the foramen magnum occipitis, and to be bounded behind 
by the tuber of the occiput and its superior transverse ridges. Its 
marks have been sufficiently dwelt upon, in the description of the os 
occipitis. 

The third oval will be described in detail in a short time. 

On the side of the head, where we consider the triangular region 
to exist, the arch formed by the malar bone and the zygomatic pro- 
cess of the temporal, forms a very conspicuous feature. The anterior 
abutment of this arch is formed by the greater part of the malar bone, 
and a considerable portion of the malar process of the superior max- 
illary. The posterior abutment is formed by the root of the zygo- 
matic process of the temporal bone. Its superior margin is thin, for 
the insertion of the temporal aponeurosis : the inferior margin is thick, 
and is divided, by a projection in its middle, into an anterior and 
a posterior surface, marking the origins of the two portions of the 
masseter muscle. There is a very considerable vacancy between the 
zygoma and the side of the head, occupied by the coronoid process 
of the lower jaw, the temporal and the external pterygoid muscles. 
The coronoid process is just within the zygomatic arch, and the tip 
rises three or four lines above its inferior margin. 

The large depression within the zygoma is the temporal fossa. 
All that portion of the side of the head, beneath the ridge called 
parietal, leading from the external angular process of the os frontis, 
and running along the surface of the parietal bone, is tributary to 
the temporal fossa. The bones, therefore, which contribute to form 
it, are the frontal, the parietal, the temporal, the great wing and the 
external pterygoid process of the sphenoid bone, and the posterior 
face of the superior maxillary and malar bones. The arrangement 
of the squamous suture is well seen in this fossa, also the junction of 
the pterygoid bone with the parietal and frontal, by the overlapping 
of the great wing of the former. At the inferior part of the latter, is 
the pointed process, from which one head of the external pterygoid 
muscle arises. 



196 



SKELETON. 



At the bottom of the temporal fossa there is a narrow slit parti- 
tioned from the nose by the nasal plate of the palate bone. This 
slit, from its position between the pterygoid process of the sphenoid 
and the upper maxillary, is called the Pterygo-maxillary fossa. It is 
triangular, the base being upwards and the point downwards. The 
base reaches to the bottom of the orbit. From the base there leads 
into the nose the spheno-palatine foramen for transmitting the lateral 
nasal nerve and blood vessels. Externally to this foramen, and 
somewhat above it, is the foramen rotundum for the upper maxillary 
nerve. On a level with the spheno-palatine foramen, and running 
horizontally through the base of the pterygoid process, is the ptery- 
goid foramen for the nerve of the same name. Running vertically 
downwards from the point of the pterygo-maxillary fossa, is the pos s 
terior palatine canal for transmitting the nerve and artery of the same 
name. The upper part or base of the pterygo-maxillary fossa, is 
continuous with a large fissure in the bottom of the orbit called the 
Spheno-maxillary. 



SECT. V. OF THE NASAL CAVITIES. 

The nose consists of two large cavities or fossae, in the middle 
of the bones of the upper jaw, and has a very irregular surface. Its 
cavities are separated from one another by a vertical septum, con- 
sisting of the vomer and of the nasal lamella of the ethmoid bone. 
This septum presents a surface which is perfectly plain, with the ex- 
ception, that in some subjects it is slightly convex on one side, and 
concave on the other. It is deficient in front. 

The upper part of either nostril is formed by the cribriform plate 
of the ethmoid bone : in front of this the surface is very oblique, 
being made by the ossa nasi ; posteriorly there is a vertical gutter on 
the body of the sphenoid bone, in the middle of which is the orifice 
of the sphenoidal cell. The distance between the cellular part of 
the ethmoid and the septum nasi is not more than three lines. The 
double row of foramina in the cribriform plate is very well seen, 
also the foramen at its anterior part for transmitting the nasal branch 
of the ophthalmic nerve ; the groove formed by the latter on the pos- 
terior face of the ossa nasi is also very distinct. 

The bottom of either nostril, called its floor, is formed by the 
palate process of the superior maxillary and palate bones ; it is somewhat 



NASAL CAVITIES. 197 

concave, and about half an inch wide ; its width, however, is not uni- 
form as it is sometimes wider or narrower in front than it is in the 
middle. In it is seen the upper orifice of the foramen incisivum at 
the anterior point of the vomer. 

The external or orbitar surface of the nasal cavity is very irregular, 
presenting a number of projections and fossse, over which the 
Schneiderian membrane is displayed. It is formed by the upper max- 
illary, the ethmoid, the unguiform, the palate, the nasal, the lower 
spongy, and sphenoid bones. In the middle of the posterior part of 
the ethmoid is the upper meatus of the nose, a deep fossa, bounded 
above by the cornet of Morgagni, or the superior turbinated bone, 
and receiving the contents of the posterior ethmoidal cells, by one or 
more orifices. At the posterior termination of this fossa is the 
spheno-palatine foramen. The middle spongy bone forms the lower 
boundary of the ethmoid ; between it and the lower spongy or tur- 
binated bone, is the middle meatus of the nose, a fossa of consider- 
able size, but of unequal surface. At the fore part of the middle 
meatus is a vertical projection, formed by the ductus ad nasum 
and lachrymal canal. Just behind this ridge, is an interval between 
it and the anterior part of the ethmoid, through which the os unguis 
may be seen. When the middle spongy bone is broken off, imme- 
diately beneath its anterior part, a channel obliquely vertical is seen in 
the ethmoid, which leads to the frontal sinus, through the anterior eth- 
moidal cell. This cell from its peculiar shape and function, is called 
infundibulum. Behind this oblique channel is another oblique 
channel, parallel, but smaller ; in which several orifices may be found 
of the anterior ethmoidal cells. The anterior channel has, indeed, 
for the ethmoidal cells other orifices besides the infundibulum, which 
are smaller, and below the latter. It is bounded, in front by a sharp, 
thin ridge of the ethmoid, the lower extremity of which contributes 
to close the large opening into the sinus maxillare. 

Commonly about the middle of the middle meatus of the nose,, 
but varying very much in different subjects, is the orifice of the sinus 
maxillare, or antrum Highmorianum. Its precise situation and di- 
rection are so very uncertain, that its orifice is found with some 
difficulty in the fresh state, in a great number of persons. Not un- 
frequently I have seen this orifice high up, under the anterior extre- 
mity of the middle spongy bone. 

The inferior meatus of the nose is bounded above by the lower 
spongy bone, and below by the palate processes. It extends the 

17* 



198 SKELETON. 

whole length of the nostril. At the anterior part of this meatus 
above, is the orifice of the ductus ad nasum, which communicates 
with the orbit of the eye. 

The nostril presents an increased width, anterior to the points* 
where the spongy bones cease : this space is bounded on the orbitar 
side by the nasal bone, and the nasal process of the upper maxillary. 
There is an increase of transverse diameter also at the posterior part 
of the nostril, behind the points where the spongy or turbinated 
bones cease. This space is bounded externally by the nasal plate 
of the palate bone, and by the internal pterygoid process. 

The posterior nares, or orifices of the nostrils, are oval, and are 
completely separated by the posterior margin of the vomer. In the 
dried skeleton, on the contrary, the anterior nares have a common 
orifice, from the deficiency of the bony septum between them. 



SECT. VI. ORBITS OF THE EYES. 

The orbits of the eyes are the conoidal cavities in the face, pre- 
senting their bases outwards and forwards, and their apices back- 
wards ; so that the diameter of either orbit, if continued, would de- 
cussate that of its fellow in the pituitary fossa or sella turcica. Seven 
bones concur in forming the orbit, to wit, the os frontis, the os mala?, 
the os maxillare superius, the os planum, the os unguis, the os sphe- 
noides, and the os palati. Its cavity is somewhat quadrangular, be- 
sides being conoidal. The angles are particularly well marked, in 
most subjects, at its base or orifice ; which resembles an oblong, 
having its long diameter in some persons placed almost horizon- 
tally, and in others obliquely downwards and outwards. Immedi- 
ately within the orifice the cavity is enlarged, behind the projection 
of the orbitary ridge of the os frontis, and the elevation of the ante- 
rior inferior margin of the orbit, so that the greatest diameter is there 
rather vertical than horizontal. From this point the orbit decreases 
gradually in size to the sphenoidal fissure, or the superior foramen 
lacerum of the orbit which forms its apex. The internal walls of the 
two orbits are nearly parallel, in consequence of the cuboidal figure 
of the os ethmoides, which is placed between them. 

The superior face or roof of the orbit is triangular and concave : 
it is very thin, and presents but a slight septum between the eye and 
the brain. Almost the whole of it is formed by the orbitar process 



ORBITS OF THE EYES. 199 

of the os frontis, its point only being made by the little sphenoidal 
wing. The depression for the lachrymal gland, at its external ante- 
rior part, is very perceptible. The trochlea for the superior oblique 
muscle of the eye, is also well seen about six or eight lines above 
the point of the internal angular process of the os frontis. Just at 
the outer side of this depression is the foramen or notch for the supra- 
orbital' artery and nerve. The optic foramen may be seen, very 
readily, passing through the little wing of the sphenoid bone. 

The inferior face, or the floor of the orbit, is also triangular and 
concave, and is formed by the orbitar process of the upper maxillary 
bone principally; being assisted, however, at its anterior external 
margin, by a portion of the malar bone ; and, at its point behind, by 
the orbitar process of the palate bone. The latter cannot be seen 
very distinctly in the articulated bones, owing to its great depth in 
the orbit ; but, when the external side of the orbit is removed with 
a saw, its position is placed in an interesting light. The floor of the 
orbit is thinner than its roof, and forms a very slight separation from 
the maxillary sinus. It is terminated behind by the spheno-maxil-- 
lary fissure, or inferior foramen lacerum of the orbit ; a large slit, 
which, commencing at the base of the sphenoidal fissure, separates 
the great wing of the sphenoidal bone from the ethmoidal, the palate, 
and the upper maxillary bones. This fissure runs obliquely out- 
wards, so as to have its external extremity terminated by the malar 
bone. Near the external extremity is seen the commencement of the 
infra-orbitar canal, for transmitting the infra-orbitar nerve and artery. 
The external face of the orbit is also triangular, and very oblique.. 
It is formed by the malar bone, and by the orbitar face of the great 
sphenoidal wing. It is defined below by the spheno-maxillary fis- 
sure, and above by the suture which unites the frontal to the malar., 
and to the great wing of the sphenoidal bone. It is terminated, at 
the apex of the orbit, by the sphenoidal fissure. 

The internal face of the orbit is an oblong square, nearly parallel, 
as mentioned, with the corresponding face of the other orbit. It is 
formed principally by the orbitar face of the ethmoid, called the os 
planum, but at the apex of the orbit a small portion of the body of 
the sphenoid bone contributes to it, and anteriorly is the os un- 
guis. It is bounded behind by the sphenoidal fissure, in front by 
the lachrymal ridge on the nasal process of the os maxillare supe- 
rius, and above and below by the upper and lower ethmoidal sutures. 



200 SKELETON. 

In the upper of these sutures there are generally the two, sometimes 
three, orbital, or ethmoidal foramina ; the anterior of which trans- 
mits the anterior ethmoidal artery and vein, and the internal nasal 
nerve, to the nose ; the posterior transmits the posterior ethmoidal 
artery and vein to the same. 

The lachrymal fossa is well worthy of attention : it is seen to 
commence small at the upper part of the os unguis, and to increase 
in size till it is formed into a complete canal, the ductus ad nasum, 
leading to the nose, by the upper maxillary and the inferior spongy 
bones. The direction of the canal is almost vertically downwards, 
inclining very slightly backwards. It was stated, that the fossa in 
the fore part of the os unguis, is sometimes supplanted by the in- 
creased breadth of the nasal process, a fact of some importance to 
an operator for fistula lachrymalis. 



SECT. VII. OF THE FACE, TOGETHER WITH SOME REMARKS 

ON THE FACIAL ANGLE, AND ON NATIONAL PECULIARITIES. 

The anterior oval of the head extends from the frontal protube- 
rances to the base of the lower jaw, and from the malar bone of one 
side to the malar of the other inclusively. This oval is divided into 
two symmetrical or equal halves, by the vertical suture, which unites 
the bones of the opposite sides of the face. 

In the infant, the frontal protuberances are always well marked, 
from their being the centres of ossification for the two halves of the 
os frontis ; in the adult, they are frequently not raised above the 
common level of the bone. The superciliary protuberances just 
above the internal half of the orbitary or superciliary ridges, are 
generally somewhat prominent, but they vary very much in this re- 
spect in different individuals. Between these ridges the frontal 
bone is sometimes raised into a vertical elevation, continuous with 
the dorsum of the nose, as is more frequently seen in young 
persons. 

The nose, or pyramidal convexity, formed by the nasal processes 
of the superior maxillary, and by the nasal bones, is concave above, 
and extremely prominent below. The prominence of it depends 
upon the development of the ossa nasi. I have frequently seen the 



THE FACE. 201 

latter curtailed to about one-half, and even one-third of their usual 
breadth, and also diminished in length ; which is followed by an 
unusual flatness of the nose: the peculiarity had been presented to 
me till lately only in negroes ; but, since then, I have also met with 
it in the skulls of white subjects: it is, however, much more uncom- 
mon in the latter. The anterior orifice of the nose is cordiform, the 
base being below: the centre of the base is marked by a rough point, 
called the anterior nasal spine. 

The cheek bones form, on either side of the face, a considerable 
prominence, depending much upon the length of the malar process 
of the upper maxillary bones. In savage tribes, this prominence is 
frequently a characteristic trait, and may depend upon the greater 
development of the upper maxillary sinuses, probably from the 
more intense employment of the organs of smelling and of masti- 
cation. The elevation of the cheek bone is always conspicuous 
in emaciated subjects, from the fat around its base being ab- 
sorbed. 

The alveolar processes with the teeth produce, in certain subjects, 
a very prominent projection in the face; varying, however, con- 
siderably in different individuals, and in different tribes of human 
beings. There is but little doubt of the organization of some men 
being more coarse and animal than that of others, even in members 
of the same family. The circumstance occasionally manifests itself 
by unusually large and long teeth, and by alveolar processes of cor- 
responding dimensions. Savage nations have almost invariably 
this peculiarity, which is kept up among them, not only by heredi- 
tary influence from father to son, but also by the actual habits of 
the individual being productive of, and favourable to this arrange- 
ment. It would be interesting to know whether from their articles 
of food generally being harder to masticate than such as are used 
by civilized people, they do not contribute to, or even produce a 
greater development in the organs of mastication. Analogy is in 
favour of the opinion, because the arms or the legs are always de- 
veloped in proportion to the vigour and frequency of the exercise 
to which they are put. Ploughmen have large legs. Blacksmiths 
have large arms. Persons whose habits of exercise do not call 
into action any part of the body, to the exclusion of other parts, 
have finer and more graceful forms than labourers. It is therefore, 
probable, that the ease and gracefulness of movement, said to mark 



202 SKELETON. 

the polished and accomplished man of fashion, depend upon the 
harmonious action of his whole frame, derived from this propor- 
tionate development of all its parts. Besides the influence of exer- 
cise upon the organs of mastication, the passions or faculties of the 
mind not (.infrequently manifest themselves there. Individuals of 
unusual ferocity and savageness, have frequently large teeth and 
alveolar processes. The gnashing of the teeth has, in all ages, 
been considered one of the most striking signs of anger. 

While speaking of these indications of man in a savage and un- 
cultivated state, it will be understood that I allude to suoh tribes as 
are engaged in the chase, and in other active modes of subsistence, 
and whose habits are not settled down into the agricultural or pas- 
toral condition. It is quite possible for one in the latter situation 
to be equally uninstructed, on every point of mental improvement, 
and to be much inferior in capacity, to one of the former ; yet his 
articles of food, and the sensations and passions in which he in- 
dulges, will give no very prominent outline to his face, but only 
stamp it with the general expression of dullness and ignorance. 

The outline of the face is marked also by depressions or fossce. 
Those for the eyes and for the nose have been studied, and arrest 
at once the attention of the most superficial inquirer. Immediately 
below the orbit is the canine fossa formed in the centre of the 
front of the upper maxillary bone. Just above the incisor teeth 
of this bone is the superior incisive fossa. Below the inferior 
incisor teeth, on each side also, is the inferior incisive fossa. 

In most adults the face projects somewhat beyond the cranium, 
but there is a considerable diversity in this respect between diffe- 
rent tribes of human beings. Camper,* who has paid much atten- 
tion to this arrangement, has designated it under the term of the 
facial angle,] which he marks off- by two straight lines. One is 
drawn from the lower front part of the frontal bone to the point 
called the anterior nasal spine at the orifice of the nose, and between 
the ends of the roots of the incisor teeth of the upper jaw; the olher, 
from this latter point to the middle of the meatus auditorius externus, 
or thereabouts. The facial angle is included between these two 

* Dissertation sur les Differences du Visage chez les Homraes. Utrecht, 
1791. 
f Anat. Atlas. Fig. 68. 



FACIAL ANGLE. 203 

lines. In Caucasian, or European heads, this angle is about eighty 
degrees. In the negro, or Ethiopian, it is about seventy degrees; 
and in the Mongolian or copper-coloured man, about seventy-live 
degrees. 

An invariable relation is established between the degrees of the 
facial angle, the capaciousness of the cranium, and the size of the 
nasal and palatine cavities. The nearer the approach is to a rec- 
tangle, the smaller is the cavity of the nose, and of the mouth, and 
the greater is that of the cranium, thereby manifesting a more vo- 
luminous and intellectual brain. On the contrary, the more acute 
that the facial angle is, the smaller is the volume of brain, and the 
larger are the nose and mouth. This is so frequently the case, that 
Bichat considers it almost a rule in our organization, that the de- 
velopment of the organs of taste and smell, is in an inverse ratio to 
that of the brain, and consequently to the degree of intelligence. 

This, like other general rules, is subject to exceptions, in conse- 
quence of the facial angle varying in its size, from causes which have 
no connexion with the degree of development of the brain. Thus 
an unusual prominence and thickness in the lower part of the os 
frontis, from an increased capaciousness of the sinuses, will make 
the facial angle appear less acute. The absorption of the alveolar 
processes, after the loss of the teeth, will produce the same result in 
our measurements of the facial angle. The heads of infants, previ- 
ously to the appearance and full growth of the teeth, have always 
the facial angle less acute than the heads of adults : in some cases an 
angle of ninety degrees is presented in them. On the contrary, a 
growth of teeth, and consequently of the alveolar processes, dispro- 
portionate to the size of the body of the upper jaw, will cause the 
facial angle to project very considerably even in an individual of the 
Caucasian race. Similar objections may be brought against the in- 
dications of the inferior line. The fair state of this argument appears 
then to be, that the doctrine of the facial angle, though correct in a 
majority of instances, has numerous exceptions from individual pe- 
culiarities, and that there is no race of human beings which does 
not present the facial angle in all its ranges from seventy to ninety 
degrees. 

With the view to meet such objections and establish a rule of 
more uniformity, M. Cuvier has proposed to ascertain results from 
a vertical section, by which it appears that the Caucasian cranium 



204 SKELETON. 

is four times the area of the face ; whereas in the negro the face is 
a fifth larger than the Caucasian face by the same rule of measure- 
ment. 

In regard to the various configurations of the human face and 
stature, depending upon habits and circumstances continued through 
a long succession of ages and generations, the following views of 
one,* pre-eminently qualified to judge, and of the highest authority, 
will not be uninstructive. 

" Although there appears to be but one human species, since all 
its individuals can couple promiscuously, so as to produce a pro- 
lific offspring ; we yet remark in it certain hereditary conforma- 
tions, which constitute what are called races. Of these there are 
three which are eminently distinct in appearance: they are, the 
white or Caucasian ; the yellow or Mongolian ; the negro or Ethio- 
pian. 

" The Caucasian race, to which we belong, is distinguished by 
the beautiful oval form of the head ; and it is this which has given 
birth to the most civilized nations, and to those which have generally 
ruled over the others. It has some differences in the shade of the 
complexion, and in the colour of the hair. 

" The Mongolian is known by its prominent cheek bones, flat 
face, narrow and oblique eyes, straight and black hair, thin beard, 
and^ olive complexion. It has formed vast empires in China and 
Japan, and has sometimes extended its conquests on this side of 
the Great Desert; but its civilization has always remained sta- 
tionary." 

The Negro race is confined to the south of Mount Atlas; its com- 
plexion is black, its hair woolly, its skull compressed, nose flattish ■ 
its prominent mouth and thick lips make it manifestly approach the 
monkey tribe ; the people which compose this race have always re- 
mained in a state of barbarism. 

"The race from which we are descended is called Caucasian, 
because tradition and also the lineage of nations, would appear to 
trace it to the group of mountains situated between the Caspian and 

* Regne Animal, par M. le Chev. Cuvier, torn. 1, p. 91. Paris, 1817. 



THE FACE. 205 

the Black Sea, (on the borders of Europe,) from whence it has 
radiated in every direction. The people of Caucasus, as also the 
Georgians and Circassians, are considered, even at the present day, 
the handsomest in the world. The principal branches of this race 
are distinguishable by the analogies of language. The Armenian or 
Syrian division, directed its course towards the south, and has given 
birth to the Assyrians, the Chaldeans, and the untameable Arabs, 
who, after Mahomet, were very near becoming masters of the world ; 
to the Phcnicians, the Jews, and the Abyssinians, which were Arabian 
colonies ; and it is very probable that the Egyptians also are descended 
from the same source. It is from this branch, (the Syrian,) always 
inclined to mysticism, that the most widely extended religions have 
sprung. Science and literature have nourished among them occa- 
sionally, but always under fantastic forms, and with a figurative 
style. 

" The Indian, German, and Pelasgic branch, is infinitely more 
extended, and was divided at a much earlier period ; we, neverthe- 
less, recognise the greatest resemblance between its four principal 
languages; which are, the Sanscrit, at present the sacred language 
of the Hindoos, and mother of all the dialects of Hindostan ; the 
ancient language of the Pelasgi, which is the common mother of the 
Greek, the Latin, of many tongues which are now extinct, and of 
almost every language spoken in the south of Europe ; the Gothic 
or Teutonic, from which are derived the languages of the North and 
North West, such as the German, Dutch, English, Danish, Swedish, 
and their dialects; and lastly, the language called Sclavonian, from 
which come those of the north-east, as the Russian, Polish, Bohe- 
mian, &c. 

"It is this great and respectable branch of the Caucasian race } 
which has carried farthest Philosophy, the Arts and Sciences, and 
which has been for ages the depository of them. 

" This branch was preceded in Europe by the Celts, who came 
from the north, and were formerly very much extended, but are now 
confined to the most western parts; and by the Cantabrians, who 
passed from Africa into Spain, and are, at present, almost confounded 
with the numerous nations whose posterity has been blended in this 
peninsula. 

"The ancient Persians have the same origin with the Indian 
branch; and their descendants, even at the present day, bear the 
strongest marks of affinity to the European nations. 

Vol. I.— 18 



206 



SKELETON. 



" The Scythian or Tartarian branch, first directing their course to 
the north and north-east, always led erratic lives in the vast plains of 
those countries: and they have only left them to return and destroy 
the more comfortable establishments of their brethren. The Scythians, 
who, at so remote a period of antiquity, made irruptions into Upper 
Asia ; the Parthians, who destroyed there the power of the Greeks 
and Romans ; the Turks, who overthrew there that of the Arabs, 
and subjugated in Europe the unhappy remnant of the Greek na- 
tion, were swarms of this stock; the Finlanders and the Hunga- 
rians are colonies of it, in some measure astray among the Sclavonian 
and Teutonic nations. The north and east of the Caspian Sea, their 
original country, are still inhabited by people of the same origin, and 
speaking similar languages ; but they are there intermixed with an 
infinity of other petty nations, of different origins and languages. 
The Tartar nation has always remained more unmixed in all that 
tract of country, extending from the mouth of the Danube, to be- 
yond the Irtisch, from which they so long threatened Russia, and where 
they have at last been subdued by her. The Mongolians, however, 
in their conquests have blended their blood with these people, and 
many traces of this intermixture are discovered, principally among 
the Western Tartars." 

" The Mongolian race commences to the east of this Tartar branch 
of the Caucasian, and prevails thence to the Eastern Ocean. Its 
branches, the Calmucks and Halkas, still nomadic or unsettled oc- 
cupy the Great Desert. Thence have their ancestors, under Attila, 
under Genghis, and under Tamerlane, spread far and wide the terror 
of their name. The Chinese come from this race, and are not only 
the most anciently civilized of it, but, indeed, of any nation yet 
known. A third braneh, (the Montchoux) has recently conquered 
China, and continues to govern it. The Japanese and Coreans, and 
almost all the hordes which extend to the north-east of Siberia, 
under the domination of Russia, belong also to it in a great measure. 
If we except a few Chinese literati, the whole Mongolian race is 
universally addicted to the different sects of the worship of Fo. 

" The origin of this great race appears to have been in the Atlay 
Mountains,* as ours was in the Caucasian ; but it is impossible to< 
follow so well the clue of its different branches. The history of these' 

* A range in the north of Asia, about 5000 miles long. 



THE FACE. 207 

wandering people, is as fugitive as their establishments ; and the 
records of the Chinese, from being confined to their own empire, 
afford us but short and vague accounts of their neighbouring nations. 
The affinities of their languages are also but too little known to guide 
through this labyrinth. 

" The languages of the north of the peninsula beyond the Ganges, 
and also that of Thibet, bear some affinity to the Chinese, at least, 
in their monosyllabic nature, and the people who speak them are 
not without traits of resemblance to the other Mongolian nations ; 
but the south of this peninsula is inhabited by the Malays, a much 
handsomer people, w r hose race and language are spread over the 
coasts of all the islands of the Indian Archipelago, and have occu- 
pied almost all those of the Southern Ocean. On the largest of the 
former, especially in the uncultivated and savage parts, we find 
other men, who have woolly hair, black complexion, and negro 
visage, and who are all extremely barbarous. The most known 
are the Papuas, a name by which they may be generally denomi- 
nated. 

"It is not easy to refer either the Malays or Papuas, to any one 
of the three great races ; but can the former be plainly distinguished 
from their neighbours, the Caucasian Hindoos on one side, and the 
Mongolian Chinese on the other ? We must confess that we do not 
find them to possess sufficient characteristics to enable us to answer 
this question. Are the Papuas negroes, who formerly straggled 
along the Indian Ocean ? We have neither drawings nor descrip* 
tions sufficiently clear to reply to this question. 

" The inhabitants of the north of the two continents, the Sa- 
moiedes, the Laplanders, and the Esquimaux, sprung, according to 
some authorities, from the Mongolian race. Agreeably to others, they 
are but a degenerate offspring of the Scythian and Tartarian branches 
of the Caucasian race. 

"It is impossible to refer, satisfactorily, the Americans themselves 
to either of our races of the old continent ; and yet they have not 
characteristics precise and constant enough to constitute a distinct 
race. Their copper-coloured complexion is not sufficient ; their 
hair, which is generally black, and their scanty beard, would lead 
us to refer them to the Mongolians, did not their well marked 
features, and their moderately prominent noses, oppose such an ar- 
rangement ; their languages are as innumerable as their tribes, and 



208 



SKELETON. 



we have yet been unable to discover either any analogies among 
them, or with those of the ancient world."* 



SECT. VIII. — OF THE DEVELOPMENT OF THE FCETAL HEAD.f 

The foetal head, in very early stages of gestation, forms an oval 
vesicle, constituting the greater part of the bulk of the embryo, and 
at this period has the face scarcely visible. The parietes of this 
vesicle are formed by a thin membrane, consisting of two layers, 
the external of which is the pericranium, and the internal layer is 
the dura mater. These layers adhere so closely that they cannot be 
accurately separated by the knife. 

About the third month of the embryo, or even earlier, ossification 
may be seen at several points of the cranium, but more extensively 
about its base. These points are the centres of ossification, which 
progressively increase towards their respective circumferences, by 
the deposite of new bony matter. Generally the base of the cranium 
begins to ossify before the vault, and is entirely ossified at birth, 
with the exception of a few parts, as the clinoid processes and the 
ethmoid bone. 

The following nuclei of ossification show themselves between the 
laminae of the foetal cranium, from the third to the fourth month. 
One at the anterior part, for the centre of either side of the os fron- 
tis ; one for the centre of each parietal bone, on the upper side of 
the head ; one on the side of the head below, for the squamous por- 
tion of the temporal bone ; and there are several for the occipital 
bone. These points extend themselves in radii ; and, as the inter- 
vals between the latter become wider by their divergence, new radii, 
as observed elsewhere, are deposited between them. In some of 
the bones, the radii, from opposite points, in the progress of ossifica- 
tion before and after birth, meet and coalesce : this occurs in the os 
frontis and in the os occipitis. 

* On this subject, see also Lectures on the Physiology, Zoology, and 
Natural History of Man, by W. Lawrence. London, 1822. 
Dictionnaire des Sciences Med. tome XXI. Paris, 1817. 
Histoire Naturelle-de L'Homme, par Lacapedo. Paris, 1821. 
Blumenbach de Variet. Gen. Hum. Nat. 179-1— also Decades, 1790—1814. 
1- Anat. Atlas, Fig. 69. 



F(ETAL HEAD. 209 

At birth the contiguous margins of the flat bones simply approach 
each other, but have not interlocked. These bones consist then of 
but one table, the edges of which are very finely serrated, and there- 
by show the radii of ossification. The edges are held together by 
the dura mater, internally, and the pericranium, externally ; but the 
fissure between them is very obvious, and so large that it allows 
very readily considerable motion and the mounting of one bone 
upon the other by slight pressure. It is always to be observed that 
the base of the cranium is an exception to the latter rule, both from 
the breadth of its articulating surfaces, and from its comparatively 
advanced ossification. In parturition, therefore, the vault of the 
cranium, by its mobility, is adjusted to the contour of the pelvis, 
but the base does not yield in either of its diameters to the expulsive 
powers of the uterus. The latter provision, however inconvenient 
in parturition, is of the greatest consequence immediately after- 
wards ; for without this immobility in the base of the cranium, 
whenever the weight of the head was thrown upon it, the pressure 
of the vertebral column would drive it upwards, to the injury of the 
brain and of the nerves proceeding from it. This resistance, it may 
be added, is still farther assisted by the arched figure of the base of 
the cranium. On this subject, it is not a little remarkable, that even 
the heads of the hydrocephalic fcetuses have the bones of the base 
fully ossified, and in contact, so as to support the weight of the head 
in the vertical position. 

Fontanels. — In consequence of the flat bones of the cranium ossi* 
tying always towards the circumference, their angles, as observed, 
being the longest radii from their centres, are the last in ossifying. 
These angles are commonly incomplete at birth, and the membra* 
nous spaces which represent them are the Fontanels. Of these 
there are six, two on the middle line of the head, above, and two 
on either side. The former afford highly important indications to 
the midwife. 

The anterior fontanel is the largest of all. . It is at the fore part 
of the sagittal suture, and is produced by a deficiency in the angles 
of the parietal bones, and of the contiguous angles of the os frontis. 
It is quadrangular or lozenge-shaped ; and the anterior angle is 
generally longer than the others. This is remarkably the case, 
when the sagittal suture is continued down to the root of the nose. 
The posterior fontanel is at the other extremity of the sagittal su- 
ture, and as there are only three points of bone defective there, tws 

IS* 



210 



SKELETON. 



for the parietal bones, and one for the occipital, this suture is trian- 
gular. In many children, at birth, it is so far filled up as to be 
scarcely visible ; the three membranous sutures, however, which 
lun into it, make its position sufficiently discernible by the finger. 

Of the two fontanels, on either side, one is placed at the angle of 
the temporal bone where it runs up between the occipital and the 
parietal. The other is in the temporal fossa, under the temporal 
muscle, at the junction between the parietal and the sphenoidal 
bones. These two fontanels are but little referred to by the ac- 
coucheur in delivery, as they are irregular and indistinct. The 
pulsations of the brain may be readily felt through the fontanels. 
They ossify rapidly after birth, and are frequently closed completely 
by the end of the first year; but if there be an accumulation of 
water in the ventricles of the brain, they remain open for an inde- 
finite period. 

The longest diameter of a child's head is from the vertex or pos- 
terior extremity of the sagittal suture to the chin, and measures five 
inches and a quarter. From the middle of the frontal bone to the 
tubercle of the occipital is four inches, from one parietal protuber- 
ance to the other is about three inches and a-half. 

At birth the os frontis consists, most commonly, of two pieces, 
united by the sagittal suture. The parietal bone is a single piece, 
incomplete at its angles. The temporal bone consists of three 
pieces: one is the squamous, the other is the petrous, and the third 
is a small ring which afterwards constitutes the meatus externus; 
it is deficient in styloid and mastoid processes. The os occipitis 
is in four pieces: one extends from the angle of the lambdoidal 
suture to the upper edge of the foramen magnum ; on either side 
of the foramen magnum is another, with the condyle growing on 
it, and the cuneiform process is the fourth. The ethmoid bone is 
cartilaginous. The sphenoidal bone is in three pieces. The body 
and little wings, being united, form one; the great wing and the 
pterygoid process, being also united, form on either side of the body 
another piece. 

At birth there is a great disproportion in size between the cra- 
nium and face. This disproportion diminishes in the progress of 
life, by the development of the sinuses and of the alveolar processes 
in the latter. At birth, indeed, there is no cavity either in the 
sphenoidal, the frontal, or the upper maxillary bones ; the orbitar 
and the palate plates are very near each other, and the rudiments 



HYOID BONE. 211 



of the teeth are hidden in the bodies of the upper and lower jaw 
bone. The latter consists of two pieces, united by cartilage at the 
chin, and its angle is very obtuse. 



CHAPTER IV. 
The Ilyoid Bone, (Os Hyoides, Hyoide.*) 

The Os Hyoides is placed at the root of the tongue, within the 
circle of the lower jaw. It is an insulated bone, having no con- 
nexion with any other, except by muscles and ligaments. It is 
said, very properly, to resemble the letter U, and consists of a body 
and of two cornua. 

The body is in the middle ; it is the largest part of the bone, and 
forms nearly a semicircle. Its anterior face is convex, and its upper 
part is flattened by the insertion of the muscles from the lower jaw, 
as the genio hyoideus and the genio hyoglossus. The posterior 
face is concave, adjusting it to the superior margin of the thyroid 
cartilage. 

The cornua, one on either side, are about an inch long, and are 
placed at the extremities of the body, being united to it by the in- 
terposition of cartilage and ligamentous fibres. They are flattened 
above and below rather than cylindrical, and diminish towards the 
posterior extremities, where they terminate in a round enlargement 
like a head. 

At the cartilaginous junction of the cornu and body, on each 
side, there is a small cartilaginous body three or four lines long, 
fastened by ligamentous fibres. It is frequently found ossified. 
This is the appendix or lesser cornu. A round ligament passes 
from it to the extremity of the styloid process of the temporal bone. 

Sometimes the ossification of the appendix extends along the sub- 
stance of this ligament for half an inch or an inch, but it is generally 
flexible at the root. 

The texture of this bone is cellular, with a thin compact lamina 

* Anat. Atlas, Fig. 70. 



212 



SKELETON. 



externally. M. Portal says, that he has found it carious from vene- 
real contamination; in which case, the patient had been afflicted 
with violent sore throat and purulent expectoration. Sauvages and 
Valsalva have each met with a case, where, from luxation of the 
cornu, the patient spoke with great difficulty. The ligament to the 
styloid process is, in some rare instances, ossified to so conside- 
rable an extent, as to produce serious difficulty in swallowing 
and in talking. 



CHAPTER V. 

Of the Upper Extremities, 

This portion of the skeleton is divided on either side of the body, 
into shoulder, arm, fore arm, and hand. 

SECT. I. — OF THE SHOULDER. 

The shoulder consists of two bones, the clavicle and the scapula, 
and occupies the superior, lateral, and posterior part of the thorax. 
Its shape and position are such, that it augments considerably the 
transverse diameter of the upper part of the trunk, taken as a 
whole : while the thorax alone, at this place, is actually smaller 
than it is below. The clavicle is longer, in proportion, in the 
female than in the male, which increases in her the transverse extent 
of the shoulder, and gives a greater space on the front of the thorax 
for the development of the mamma?. This coincidence between 
the length of the shoulder and the development of the mamma, has 
been particularly noticed by Bichat, who says that it is almost 
always well marked, that very rarely a voluminous bosom reposes 
on a small pectoral space, or a small bosom is found upon a large 
pectoral space. In the male, on the contrary, this diameter of the 
trunk is increased principally by the breadth of the scapula, which, 
from its position on the thorax, and its great size, gives the bulky 



THE SHOULDERS. 213 

appearance to this part. It is evident that these modifications in 
the frame-work of the shoulders, are connected with the natural 
destinations of the two sexes. In woman the length of the clavicle 
is adverse to its strength, and it is indistinctly marked by muscular 
connexions; whereas, in man it is short, strongly marked, and 
large. Anatomists who are fond of extending such comparisons, 
say, also, very justly, that the pubes, which perform the same office 
for the lower extremities that the clavicles do for the upper, that of 
keeping the two apart, are, in the female, both smaller and longer 
than in the male; that their shape is not so favourable to strength 
or locomotion, and has a special view towards the lodgement of the 
genital organs, and to the passage of the child. In man the in- 
creased size of the whole skeleton, and the greater development of 
the muscular system, indicate that he was intended for more labori- 
ous exertion than the female. 

The thorax and the shoulder are connected by a reciprocal develop- 
ment, both being indicative, when large, of a robust and vigorous 
constitution ; and when small, of a weakly one. As both of these 
parts are acted on by the same muscles, the necessity of this coinci- 
dence is sufficiently apparent. The height of the shoulder depends 
upon the scapula alone ; its elevation, therefore, is greater in males 
and in vigorous persons generally, than in females and in weakly 
individuals. The direction of the shoulder is such, that the articular 
face of the scapula for the os humeri, looks outwards, thereby proving 
that the quadruped position in man is unnatural ; for by it, the 
weight of the fore part of the trunk is directed upon the back part of 
the capsular ligament of the joint instead of upon the glenoid cavity, 
as in quadrupeds. This, and many other circumstances, prove that 
the natural intention of the upper extremities in the human subject, 
is to seize upon objects, and not to maintain the horizontal posi- 
tion, 



Of the Shoulder Blade, (Scapula, Omoplate.*) 

The Scapula is placed upon the posterior superior part of the 
thorax, and extends from the second to the seventh rib inclusively : 

* Anat. Atlas, Figs. 71, 72. 



214 SKELETON. 

its posterior edge is nearly parallel with the spinous processes of the 
vertebrae, and not far from them. 

Its general form is triangular. It therefore presents two faces, 
of which one is anterior, and the other posterior, — three edges, of 
which one is superior, another external, and the third internal or 
posterior — and three angles, of which one is superior, another in- 
ferior, and the third exterior or anterior. 

The posterior face of the scapula is called its dorsum ; is some- 
what convex, when taken as a whole ; and is unequally divided by 
its spine into two surfaces or cavities, of which the lower is twice 
or three times as large as the upper. The spine is a very large 
process that begins at the posterior edge of the bone, by a small 
triangular face ; rapidly increases in its elevation and running 
obliquely towards the anterior angle, ceases somewhat short of it ; 
it is then elongated forwards and upwards, so as to overhang the 
shoulder joint, and to form the acromion process. The cavity 
above the spine is owing principally to the elevation of the latter, 
and is called the fossa supra-spinata ; it is occupied by the supra- 
spinalus muscle. The cavity below the spine is the fossa infra- 
spinata, and is for the infra-spinatus muscle : it is bounded below 
by a rising of the external margin of the bone. The middle of this 
fossa presents a swell or convexity, which is a portion of the gene- 
ral convexity presented by the posterior face of the bone. The spine 
of the scapula is always prominent in the outline of the shoulder, 
and has a well secured base along the whole of its attachment to the 
bone, to where it terminates in the acromion process. It leans up- 
wards, and from the increased breadth of its summit, is concave 
both above and below. The summit itself is somewhat rough, and 
has inserted into its superior margin the trapezius muscle, while the 
inferior margin gives origin to the deltoid. The little triangular 
face at the commencement of the spine is made by the tendon of 
the trapezius muscle gliding over it. The acromion process arises 
from the spine by a narrow neck, is triangular, nearly horizontal, 
and overhangs the glenoid cavity, being elevated about one inch 
above it. It is slightly convex above and concave below : the external 
and the internal margins are the longest. The posterior margin is 
continuous with the inferior edge of the spine of the scapula ; and the 
internal is on a level with the clavicle. At the fore extremity of the 
internal margin, is a small, oval, articular face, by which the aero- 



THE SHOULDERS. 215 

mion unites with the clavicle. The margins of the acromion, with 
the exception of the internal, are rough, and give origin to the del- 
toid muscle. 

The anterior or costal face of the scapula is concave, and obtains 
the name of the sub-scapular fossa or the venter. It is occupied by 
the sub-scapular muscle ; the divisions of which, by leaving deep in- 
terstices between them, produce corresponding ridges upon the bone 
that run obliquely upwards and outwards. Along the whole pos- 
terior margin of this face of the scapula, is inserted the serratus 
major anticus. 

The posterior or vertebral margin of the scapula is the longest of 
the three, and is called the base. It is not perfectly straight, but 
somewhat rounded, especially above the spinous process ; and has 
there varied degrees of obliquity in different persons. This margin, 
below r the spine, receives the rhomboideus major muscle, and above 
the spine, the levator scapulae ; at the part between the other two, 
the rhomboideus minor is inserted. 

The external or axillary margin of the scapula, also called the 
inferior costa, is much the thickest of the three. A superficial fossa 
placed somewhat posteriorly, forming the inferior boundary of the 
fossa infra-spinata, begins about two inches from its inferior extre- 
mity, and running up to the neck of the bone, lodges the teres minor 
muscle. On the exterior face of the inferior angle is a flat surface, 
from which the teres ma^or muscle and a slip of the latissiraus dorsi 
arise and at the fore part of this surface the inferior costa is elon- 
gated into a kind of process. Just below the glenoid cavity is a 
small ridge for the origin of the long head of the triceps muscle. 

The superior margin or costa of the scapula, is the shortest and 
thinnest of the three, and is terminated in front by the coracoid 
notch between it and the coracoid process. The notch is convert- 
ed into a hole by a ligament, in the living state, and through it 
pass the supra-scapular nerve and blood-vessels. 

The glenoid cavity for articulating with the os humeri, supplies 
the place of the anterior angle of the scapula. It is very superfi- 
cial, and ovoidal, with the small end upwards. Just at the upper 



216 SKELETON. 

end is a small flat surface, from which the long head of the biceps 
arises. The glenoid cavity is fixed on the neck or cervix, as it is 
called, at which a general increase in the thickness of the bone 
occurs, in order to give a strong foundation to this cavity. From 
the superior part of the cervix arises the coracoid process, the base 
of it being bounded in front by the glenoid cavity, and behind by 
the coracoid notch. The base rises upwards and inwards for half 
an inch, and what remains of the process, then, runs horizontally 
inwards and forwards, to become smaller, and terminate in a point. 
This point is advanced beyond the glenoid cavity, about an inch 
from its internal margin. The upper surface of the coracoid pro- 
cess is rough and undulated; below it is concave, forming an arch 
under which passes the sub-scapularis muscle. On the clavicular 
side of its base is a tuberosity, from which arises the conoidal liga- 
ment. The extremity is marked by three surfaces: the interior is 
for the insertion of the pectoralis minor, the middle for the origin 
of the coraco-brachialis, and the external for that of the short head 
of the biceps. The acromial margin of the coracoid process gives 
origin to the triangular ligament of the scapula, which is inserted 
into the acromion just below the face for the clavicle. 

The scapula is composed of cellular and compact substance. 
The two laminae of the latter are in contact in the fossa supra-spinata, 
and infra-spinata; from which cause the bone is diaphanous at these 
points. 



Of the Clavicle, (Clavicula, Clavicule.*) 

The Clavicle is a long bone, situated transversely at the upper 
front part of the thorax, and extends from the superior extremity of 
the sternum to the acromion of the scapula. It is cylindrical in its 
middle third, flattened at its external, and prismatic or triangular 
at its sternal extremity. Besides being shorter, it is more crooked 
and robust in man than in woman, and different individuals present 
it under considerable varieties of curvature. The sternal two-thirds 
of it are convex in front, and concave behind, while the humeral 
third is concave in front, and convex behind: this double curvature 
induces anatomists to compare it with the letter S, though it is by 
no means so crooked. 

* Anat. Atlas, Fig. 73. 



THE ARM. 217 

We have to consider its superior and inferior face, its anterior, 
and posterior edge, and the two extremities. The superior face is 
smooth, and does not present any marks of importance excepting a 
depression near the sternum, for the origin of the sterno-cleido mas- 
toid muscle. The inferior face, near the sternal end, has a rough 
surface, to which is attached the costo-clavicular or rhomboid liga- 
ment : about fifteen lines from the humeral extremity is a rough 
tubercle for the attachment of the coraco-clavicular or conoid liga- 
ment. Between the two ends, a superficial fossa is extended for 
lodging the sub-clavius muscle. The sternal two-thirds of the 
anterior margin are marked by the origin of the pectoralis major ; it 
is there thick; the other part of this margin is thinner and gives 
origin to the deltoid muscle. The posterior margin presents, near 
its middle, one or more foramina for the nutritious vessels. The 
triangular internal end of the clavicle is unequal where it joins the 
sternum, and is elongated considerably at its posterior inferior corner. 
The external flat end presents at its extremity a small oval face, cor- 
responding with that on the acromion scapulas. 

This bone is very strong from the abundance of its condensed 
lamellated structure ; but, like other round bones, the cellular mat- 
ter predominates at its extremities. 



sect. ii. — of the arm, (Os Humeri, & Humerus.*) 

The arm extends from the shoulder to the elbow r , and has but one 
bone in it, the os humeri. The latter, in its general appearance, is 
cylindrical, w r ith an enlargement of both extremities; the superior 
end presents a general swell, while the inferior is flattened out. 

The superior extremity of the os humeri, which is also called its 
head, is very regularly hemispherical, and has its axis directed ob- 
liquely upwards and backwards, to apply itself with more facility to 
the glenoid cavity of the scapula. The base on which the head 
reposes is termed neck, it is not more than four or five lines long, 
and is marked off by a superficial furrow, surrounding the bone. 
This furrow is more conspicuous above, where it separates the head 
from two knobs called the tuberosities. 

One of these tuberosities, the external, being placed beneath the 

* Anat. Atlas, Fig. 74. 
Vol. I.— 19 



218 



SKELETON. 



acromion scapulae, is much larger than the other, and bears on its 
upper face the marks of the tendinous insertion of three muscles. 
The most internal mark is for the supra-spinatus scapulae, the middle 
for the infra-spinatus, and the external, or posterior, for the teres 
minor. The smaller tuberosity is internal, and placed on a line with 
the coracoid process ; it has but one mark, and that is on its upper 
face, for the tendinous insertion of the sub-scapularis muscle. The 
two tuberosities are separated by a deep fossa, named bicipital, from 
its lodging the tendon of the long head of the biceps muscle. This 
fossa is continued, faintly, for some inches down the os humeri ; its 
lower part being bounded, externally, by a rough ridge, indicating 
the insertion of the peetoralis major, and internally by another ridge, 
not quite so strong or rough, indicating the insertion of the teres 
major and latissimus dorsi. 

The body of the os humeri is the part extended between its ex- 
tremities. The superior half presents a more cylindrical appearance 
than the inferior, which is rather triangular. On the middle of the 
bone, externally, two inches below the insertion of the peetoralis 
major, exists a triangular elevation into which the deltoid muscle is 
inserted. At the internal margin of the bone, and on a transverse 
level w T ith this insertion, is the insertion of the coraco brachialis mus- 
cle ; and between the two is the orifice of the canal for the nutritious 
artery. The front of the os humeri, in its lower half, is flattened on 
each side down to its inferior end ; on these surfaces is placed the 
brachialis intemus muscle. On a line with the posterior end of the 
greater tuberosity, and a little below it, an elevation is formed for 
the origin of the second head of the triceps extensor cubiti. The 
posterior face of the bone is flattened from this point down to its 
lower extremity, and accommodates the last named muscle. 

The articular surface for the elbow joint is very irregularly cylin- 
drical. The part that joins the radius, presents itself as a small 
hemispherical head, placed on the front of the bone, and with its 
axis looking forwards. Just above it, in front, is a small depression 
for the head of the radius in its flexions. The surface which articu- 
lates with the ulna, is more cylindrical, but still irregularly so; for 
its middle is depressed, while the sides are elevated: the internal 
side is much broader and more elevated than the external. The 
lesser sigmoid cavity is just above the front of the ulnar articular 
surface, and receives the coronoid process. The greater sigmoid 



THE FORE ARM. 219 

cavity is at a corresponding place behind, and receives the olecranon 
process : the bone where it separates these cavities is very thin : 
sometimes it is even deficient. 

The external condyle is just above the radial articular surface ; it 
is continuous with a ridge of three or four inches long, forming the 
external margin of the bone, and from it, and the ridge together, 
arise the extensor muscles of the fore arm and hand. The ridge, 
itself, is bounded, above, by a small spiral fossa, descending down- 
wards and forwards, made by the spiral artery and the muscular 
spiral nerve. The internal condyle is placed just above the internal 
margin of the ulnar articular surface : it is much more prominent and 
distinct than the external, and may be readily felt beneath the skin. 
A ridge also leads from it and extends upwards as high as the in- 
sertion of the coraco brachialis, but it is by no means so elevated as 
the external ridge, though it is much longer. From the internal 
condyle, and the adjoining part of the ridge, arise the flexor muscles 
of the hand and fore arm. 

The os humeri is composed of compact and cellular substance ; 
the latter predominates at the extremities, and the former in the 
body. 

SECT. III. OF THE FORE ARM. 

The fore arm is placed between the arm and the hand, and con- 
sists in two straight bones, the Ulna and the Radius, of which the 
former is on the side of the little finger, and the latter on that of the 
thumb. 

Of the Ulna, (Cubitus.*) 

The ulna, though nearly straight, is not wholly so. It is much 
larger at the upper than at the lower extremity, and in its general 
features is triangular. It has to be considered in its humeral and 
carpal extremities, and in its body. 

The humeral, or upper extremity, presents the olecranon process 
* Anat. Atlas, Fig. 75. 



220 



SKELETON. 



at its termination; the coronoid a little below and in front; the 
greater sigmoid cavity between the two ; and the lesser sigmoid on 
the radial surface of the coronoid. 

The olecranon process is rough on its upper face, for the inser- 
tion of the triceps muscle, and terminates in front in a sharp edge 
and point, which are received into the greater sigmoid cavity of the 
os humeri. The coronoid process is a triangular sharp ridge, much 
elevated, and having a large base; on the lower front of the latter 
is a roughness for the insertion of the brachialis internus muscle. 
The greater sigmoid cavity forms all the articular surface between 
the margins of the two processes. It is divided, transversely, at its 
bottom, by a superficial roughness, which distinguishes the olecranon 
from the coronoid portion of it. Besides which, a rising exists in 
its entire vertical length, which is received into the corresponding 
depression of the os humeri. The lesser sigmoid cavity has its sur- 
face continuous with that of the greater, and presents itself as a small 
semi-cylindrical concavity, for articulating with the side of the head 
of the radius. A small fossa, for fatty matter exists just above it, 
and below is a triangular excavation affording space for revolving 
to the tubercle of the radius. 

The carpal, or lower extremity of the ulna, presents, on the side 
of the little finger, a process of variable length, the styloid, from 
which arises the internal lateral ligament of the wrist. At the radial 
side of this process is an articular face or small head, one surface 
of which looks towards the wrist, and the other is in contact with 
the radius, being semi.cylindrical. On the back of the ulna, between 
the styloid process and this head, is a groove for the passage of the 
extensor carpi ulnaris tendon. 

The body of the ulna is triangular, in consequence of three ridges, 
which extend from the brachial to the carpal extremity. The first 
or most prominent of these ridges is on its radial side, and, beginning 
at the posterior end of the lesser sigmoid cavity, continues very dis- 
tinct almost to the lower end ; it then, however, gradually subsides. 
From it arises the interosseal ligament. The supinator radii brevis 
muscle, also arises from its beginning for the distance of a couple of 
inches. Within this ridge, on the anterior or palmar face of the 
bone, is a second, more rounded, which, beginning at the internal 



THE FORE ARM. 221 

margin of the coronoid process, extends down to the styloid process. 
For the greater part of its length it gives origin to the flexor pro- 
fundus digitorum, but just above the carpus, the pronator quadratus 
arises from it. The third ridge begins at the external margin of the 
olecranon, and runs in a serpentine way to the inferior end of the 
ulna, but becomes almost indistinct at its lower part. To the upper 
fourth of this ridge, is attached the anconeus muscle, which reposes 
in a hollow between it and the beginning of the first mentioned ridge. 
On the posterior surface of the bone, just below the olecranon, is a 
triangular face an inch and a-half or two inches long on which we 
lean, and which is placed just under the skin, it may, therefore, be 
readily felt in the living body. 

The three ridges of the ulna divide it into as many surfaces 
which are each modified by the muscles lying upon them. The 
anterior surface presents, just above the middle of the bone, the 
canal for the nutritious artery, running obliquely upwards. 

The body of the ulna is compact, the extremities, and more 
abundantly the upper, are cellular. 



Of the Radius, (Radius .*) 

The radius is shorter than the ulna, is placed on its external side, 
and extends from the os humeri to the wrist. It is smaller at the 
humeral than at the carpal extremity, and though nearly straight is 
somewhat arched outwardly which is rendered very distinct by ap- 
plying the ulnar margin of it, to a plain surface, and thus letting it 
rest upon the two ends of the arch. This conformation strengthens 
it, and restrains its range of motion around the ulna. It is to be 
considered in its extremities and body. 

The superior or humeral extremity presents a cylindrical head, 
which bears all around it the marks of a cartilaginous incrustation, 
broader on the ulnar than on the other side. The broader part 
plays in the lesser sigmoid cavity of the ulna, while the other is in 
contact with the annular ligament. A superficial fossa also exists 

* Anat. Atlas, Fig. 76. 
19* 



222 



SKELETON. 



on the upper surface of this head, which receives the convexity of 
the articular face of the external condyle of the os humeri. The 
head of the radius is placed upon a narrow part called the neck, of 
about half an inch in length. Immediately below the neck, on the 
ulnar side, is a rough protuberance or tubercle, the bicipital, along 
the posterior half of which is the insertion of the biceps flexor cubiti. 

The lower or carpal extremity of the bone, is augmented conside- 
rably in volume, and is flattened out transversely. The carpal sur- 
face presents a long superficial cavity, it is bounded externally by 
the styloid process, from which proceeds the external lateral liga- 
ment; and ends on its ulnar side, by a small cylindrical concavity, 
for receiving the lower end of the ulna. The former or superficial 
cavity is divided into two by a slight ridge in its short diameter ; the 
division next the styloid process receives the scaphoid bone, and 
the other the os lunare. At this extremity also a ridge exists on the 
front of the bone for forming the margin of the articular face, and 
giving origin to the capsular ligament. The posterior and external 
faces of the bone, here, are rendered irregular by several grooves 
and ridges. The large groove next to the cylindrical concavity for 
the ulna, transmits the tendons of the extensor communis digitorum 
and indicator, also the tendon of the extensor major pollicis, which 
forms a channel somewhat distinct, and on the styloid side of the 
groove. Next to this is another large groove for the tendon of the 
extensor carpi radialis brevior and of the longior; and on the sty- 
loid side of the radius is the third groove for transmitting the tendon 
of the extensor minor pollicis, and of the extensor ossis metacarpi 
pollicis. The anterior margin of this groove is formed by a small 
spine or ridge, into which is inserted the tendon of the supinator 
radii longus. 

The body of the radius is somewhat triangular, and therefore 
presents three ridges. One, on its ulnar side, extends from the bi- 
cipital protuberance to the lower end, and gives origin to the inter- 
osseous ligament ; it is sharp and well marked. Another, on the 
outer or styloid margin of the bone, also begins at the bicipital pro- 
tuberance, and terminates in the styloid process. The upper part of 
this ridge is curved, has the supinator brevis inserted into it, and a 
portion of the flexor digitorum sublimis arising from it ; at its lower 
part the pronator quadratus is inserted. The third ridge is on the 



THE HAND. 223 

posterior face of the radius, and arising insensibly from below its 
neck, is principally conspicuous in the middle third of the bone : it 
runs down, however, to the carpal extremity, and, becoming more 
prominent there, separates the two larger grooves from each other. 
This ridge is shorter, and not so elevated as the other two. 

These three ridges form as many surfaces to the radius, of which 
the anterior augmenting gradually in its descent, affords attachment 
to the flexor longus pollicis above, and to the pronator quadratus 
below ; at its upper part is a canal, slanting upwards, for the nutri- 
tious artery. The posterior surface has the extensor muscles of the 
thumb and the indicator lying upon it. The external surface pre- 
sents a roughness, just above its middle, for the insertion of the pro- 
nator teres ; and below it is covered by the radial extensors, which 
are crossed by the extensor metacarpi pollicis and the extensor 
minor. 

The body of the radius is compact ; its extremities are cellular. 



SECT. IV. — OF THE HAND.* 

The hand consists of the carpus, metacarpus, and phalanges, and 
has in its composition twenty-seven bones, to which number may be 
added the two sesamoids. 



Of the Carpus, (Carpe.) 

The carpus, or wrist, is next to the bones of the fore arm. Eight 
bones compose it, which are arranged into two rows, one adjoining 
the fore arm, and the other the metacarpus : — they are called first 
and second rows. These bones present very diversified forms, and 
a number of articular faces, which render them difficult to be dis- 
tinguished from each other. 

The first or antibrachial row has in it the os scaphoides, lunare, 
cuneiforme, and pisiforme. The second or metacarpal row has in it 
the os trapezium, trapezoides, magnum, and unciforme. 

* Anat. Atlas, Figs. 77, 78, 79. 



224 



SKELETON. 



Of the Scaphoides, (Scaphoide.) 

This bone is on the styloid half of the end of the radius, and is 
distinguishable in a set by its greater length. It is convex above 
and concave below. The convexity forms only a half of its upper 
surface, the other half being rough, and making a knob at its ex- 
tremity. The concavity on the lower surface is large enough to 
receive the end of a finger. Between the concavity and the con- 
vexity, and on the dorsal surface of the bone, at its outer end, is a 
second convexity, of an oblong shape. Between the two convex- 
ities is a small fossa for the capsular ligament. The palmar, or 
anterior face, shows a curve in the bone. The knobbed extremity 
projects beyond the styloid process of the radius. The other ex- 
tremity, which is narrow, joins the os lunare. 



Of the Lunare, (Semilunaire.) 

This bone is at the ulnar side of the preceding, and may be dis- 
tinguished by the semi-lunated shape of the surface joining the 
scaphoides. Its upper surface is convex where it articulates with 
the radius ; the lower face is concavely cylindrical. The ulnar side 
is a plain surface which joins the os cuneiforme. Its dorsal side is 
rather thinner than its palmar. 



Of the Cuneiforme or Pyramidale, {Pyramidal.) 

This bone is placed at the ulnar side of the last, and may be dis- 
tinguished by its representing somewhat a triangular pyramid. The 
surface next the lunare is a plain, but the other extremity, being the 
boundary of the wrist in that direction, is rough. Above, it pre- 
sents a small convexity, adjoining the surface for the lunare, where- 
by it enters partially into the upper wrist joint. Its inferior surface 
is concavo-convex, the convexity being towards the ulnar end. 
On its palmar side it presents a circular plain surface for the os 
pisiforme. 



THE HAND. 225 



Of the Pisiforme, (Pisiforme.) 

This bone is placed on the front or palmar surface of the last, and 
may be distinguished by its being smaller than any other in the 
carpus, by its spheroidal shape, and by its presenting but one arti- 
cular face, which corresponds "with one on the cuneiforme. It is 
always so prominent as to be felt, without difficulty, at the ulnar ex- 
tremity of the wrist, and is very moveable. 



Of the Trapezium, (Trapeze.) 

This bone is placed at the radial end of the second row ; its shape 
is exceedingly irregular, but it may be generally distinguished by 
being a bone of the third magnitude as regards the second row. It 
is better for the student to find out first the surface by which it ar- 
ticulates with the metacarpal bone of the thumb, which he can do in 
a short time by a comparison of the surfaces of the two bones. 
This being successful, will establish a clew to the other surfaces, 
and to the relative position of the bone. The thumb surface is a 
concave cylindrical trochlea, placed on the radial side of the trape- 
zium, and looking downwards and outwards. On the reversed or 
upper side is a small concavity, which receives the dorsal convexity 
of the scaphoid bone. Continuous with this concavity is another on 
the ulnar side, which receives a corresponding convexity of the 
trapezoides. Between this concavity and the one for the thumb is 
a small surface, by which the trapezium articulates partially with the 
metacarpal bone of the fore finger. The dorsal face is rough and 
unequal. The palmar face is unequally divided by a high ridge or 
process, at the ulnar side of whose root is a deep fossa for the 
tendon of the flexor carpi radialis. 



Of the Trapezoides, (Trapezoide.) 

It is placed at the ulnar side of the last bone, and is the smallest 
in the second row. There is no liability of confounding it with any 
other bone of the carpus, as it is the least of any, excepting the pisi- 



226 



SKELETON. 



forme. The greater difficulty is the adjustment of it in the sepa- 
rated bones : the following rule, however, will serve. It is sur- 
rounded by articular faces on its sides, but the dorsal surface 
presents a broad base, while the palmar extremity is reduced in 
size. Holding the bone with a reference to these, it will be ob- 
served that one side is very crooked and concave, while the re- 
versed or opposite one is conxex. The latter fits against the surface 
of the trapezium which has been indicated, while the former em- 
braces the side of the os magnum just below its head. The 
metacarpal surface of the trapezoides is long and elevated in its 
middle, for being received into the root of the metacarpal bone of 
the fore finger, while the upper surface presents a long concavity for 
receiving a part of the dorsal convexity of the scaphoides. 



Of the Magnum, ( Grand Os.) 

It is placed at the ulnar side of the trapezoides, and from its 
being larger than any other bone in the carpus, will scarcely be 
mistaken. Its ulnar side is flat, and presents a plain surface for 
articulating with the unciforme. The radial side is uneven and 
rather indistinctly marked where it joins the trapezoides, but the 
latter surface will be found near the middle of this side just below 
the head. The upper surface of the magnum is formed into a sphe- 
rical head, the radial side of which reposes in the concavity of the 
scaphoides, while the ulnar side is in the concavity of the lunare. 
Its metacarpal surface is triangular, convex, and winding, by which 
it joins the metacarpal bone of the middle finger. On the radial 
side of this surface is a small one continuous with it, whereby 
the magnum articulates partially with the metacarpal bone of the 
fore finger. The posterior or dorsal face is broad, while the palmar 
is more narrow. 



Of the Unc forme, (Os Crochu.) 

It is placed at the ulnar side of the magnum, is nearly of the 
same size, but readily distinguishable from it by its long crooked 
process as well as by its peculiar shape. Its radial side is plain 
where it joins the magnum; the reversed or ulnar side is brought 



THE HAND. 227 

to a thin edge. The metacarpal surface presents two distinct con- 
cavities ; the one next to the ulnar edge is for the metacarpal bone 
of the little finger, and the other for that of the ring finger. The 
upper surface is convex and winding, having its ulnar margin 
almost touching the surface for the metacarpal bone of the little 
finger. The most considerable portion of the upper surface re- 
poses upon the cuneiform, and the remainder upon a part of the 
concavity of the lunare. The posterior face is broad and rough, 
while the palmar is narrower. From the ulnar side of the latter, 
projects the unciform process already alluded to. 



The two ranges of carpal bones, thus shaped, present, when ar- 
ticulated or united together, an oblong body, the greatest diameter 
of which is transverse. Its posterior face is semi-cylindrical and 
arched, while the anterior face is concave for the passing of the 
flexor tendons. Two protuberances are found on each extremity 
of the palmar surface. Those at the ulnar end are the pisiforme, 
and the unciform process of the unciforme ; those at the radial end 
are the protuberance at the radial end of the scaphoides, and the 
sort of unciform process from the trapezium bounding the radial 
margin of its groove. These several prominences may, with a little 
attention, be readily distinguished beneath the skin. The superior 
face of the carpus, which articulates with the lower end of the radius 
and ulna, presents an oblong convex head formed by the scaphoides, 
the lunare, and very partially by the cuneiform. The inferior face 
of the carpus presents a very diversified surface, subdivided into five 
distinct ones, each of which is fashioned according to the shape of 
the metacarpal bone with which it has to articulate. 

The central joint of the wrist, formed between the two rows of 
bones, is very deserving of attention. The first row is convex on 
its radial end, the convexity being formed on one half of the sca- 
phoides : to the ulnar side of this there is a deep concavity formed 
by the other half of the scaphoides, — by the lunare and the cunei- 
forme. The upper surface of the second row fits very accurately 
upon the lower surface of the first: its radial end is, therefore, a 
concavity formed by the trapezium and trapezoides, which receives 
the cqnvexity of the scaphoid ; then a very large prominent head is 



228 



SKELETON. 



formed by the magnum and unciforme, and received into the con- 
cavity of the first row. The magnum reposes upon the scaphoides 
and part of the lunare, the unciforme upon the remainder of the 
lunare, and the whole of the cuneiforme. The carpal bones consist 
of cellular matter enclosed by condensed lamellated substance. 



Of the Metacarpus. 

The metacarpus, is situated between the carpus and the phalanges 
of the fingers and thumb. It consists of five bones, one for the 
thumb and one for each finger. The latter are parallel or nearly so 
with each other; but the first diverges considerably, and is so placed 
as to traverse the others in front during its motions. These bones 
are rounded in their middle, are enlarged at their extremities, and 
are bent so as to be concave on the anterior face, and convex be- 
hind. Their sides are impsessed by the intervening muscles. That 
of the thumb is the shortest, the others decrease successively in length 
from the fore to the little finger. 

Of the First Metacarpal Bone, or that of the Thumb. — It is placed 
upon the trapezium: and besides being the shortest, is also the 
thickest of any. Its upper end is semi-cylindrical and slightly con- 
cave from side to side, to present a fit surface to the trapezium. Its 
lower end is slightly convex, and elongated in front into a trochlea, 
on either side of which reposes a sesamoid bone. The posterior 
face of its body is flat and very slightly bent ; the anterior is concave 
in its length, and is divided into two surfaces by a middle ridge. A 
roughness exists on either side, at its lower end, for the attachment 
of the lateral ligament. 

Of the Second Metacarpal Bone, or that of the Fore Finger.— The 
greater length of this bone gives it a distinctive character. It is 
placed upon the trapezoides, and articulates laterally also with the 
trapezium and the magnum. Its carpal or upper end presents, in 
the middle, a deep concavity for receiving the trapezoides, at the 
radial side of which is a small plain face for articulating with the 
trapezium, and at the ulnar side an oblong surface, the upper margin 
of which joins the magnum, and the remainder is in contact with the 
third metacarpal bone. The lower end presents a convex hejid ex- 



THE HAND. 229 

tended in front to concur in the flexion of the finger, on each side of 
which head is a concave rough surface for the lateral ligament. The 
posterior face of the bone presents a triangular flat surface, the base 
of which is towards the finger or phalangial end. The palmar face 
is concave, longitudinally, and divided by a middle ridge, into two 
surfaces, each of which is compressed by the interosseous muscles. 
A tubercle exists on the back of the bone just below its carpal end 
for the insertion of the tendon of the extensor carpi radialis longior, 
and another in front for that of the flexor carpi radialis. 

Of the Third Metacarpal Bone. — This is a little shorter than the 
last, and is nearly of the same size, but its carpal extremity is very 
different. The latter is triangular, and is bounded on its radial side 
by a sort of styloid process, with a tubercle on the posterior face of 
it, into which the tendon of the extensor radialis brevior is inserted. 
It is placed upon the magnum, to which it joins by a slightly con- 
cave, winding surface. It also presents, continuous with the same 
surface, an oblong face which joins the second metacarpal bone, and, 
on the reversed side, two round facets, which are contiguous to the 
fourth metacarpal bone. In regard to its lower or phalangial extre- 
mity and body, this bone resembles closely the one last described. 

Of the Fourth Metacarpal Bone. — This bone is placed upon the 
unciforme, and has a very small articulating surface with the mag- 
num : it is much smaller and shorter than the third metacarpal, and 
readily distinguishable by these circumstances. The carpal surface, 
by which it joins the unciforme, is triangular and slightly convex; 
its radial edge touches the magnum. Continuous with this edge are 
two small faces, slightly convex, which join the contiguous faces of 
the third metacarpal bone. On the reversed side of the fourth meta- 
carpal is an oblong face which joins the carpal end of the fifth me- 
tacarpal bone. In regard to its body and phalangial extremity, this 
bone resembles the two preceding, and therefore does not require a 
particular description. 

Of the Fifth Metacarpal Bo?ie. — It is placed upon the unciforme 
exterior to the last, and is both smaller and shorter than the fourth. 
The carpal extremity presents a cylindroid and slightly convex face, 
for articulating with the unciforme, at the radial margin of which 
is an oblong facet, for joining the fourth metacarpal: just below the 

Vol. I.— 20 



230 SKELETON. 

outer margin is a small tuberosity, into which is inserted the tendon 
of the extensor carpi ulnaris. The lower or phalangial extremity, 
like that of the others, presents a convex articular face, extended in 
front for the flexion of the first phalanx. The body also corresponds 
with that of the others, excepting that it is more flat in front. 



Of the Phalanges. 

The fingers are named numerically, beginning at the fore finger ; 
they are also named from their functions, as Indicator, Impudicus, 
Annularis, and Auricularis. 

Each finger has three bones in it, called its phalanges : the bone 
adjoining the metacarpus is the first phalanx, the middle bone is the 
second, and the other the third. 

The first phalanx is the largest. Its posterior face is semi-cylin- 
drical, the anterior face is flattened and concave in its length. The 
two surfaces run into each other by forming a ridge on either side, 
from which arises the theca of the flexor tendons. The metacarpal 
extremity is enlarged, and presents a superficial cavity, which re- 
ceives the end of the metacarpal bone. On either side of this end 
of the bone is a small tuber for the lateral ligament. The lower 
extremity is also enlarged and flattened at its sides. Its articular 
face is extended in front, and presents two condyles, or small heads, 
for joining the second phalanx. 

The second phalanx is likewise second in size and length. It is 
semi-cylindrical on its posterior face, flattened on its anterior, which 
is somewhat concave in its length, and the tw r o surfaces form a ridge, 
on either side, into which the tendon of the flexor sublimis is inserted, 
and from which arises the theca of the flexor tendons. Its extremi- 
ties are slightly enlarged : the articular face of the upper presents 
tw r o superficial cavities for the condyles of the first phalanx: the 
articular face of the lower extremity presents a trochlea, with a slight 
elevation at each side. 

The third phalanx is the smallest of the three, and is very different 
from the others. Its superior extremity being enlarged, presents an 
articular face, having tw*o superficial cavities, which adjust themselves 
to the corresponding face of the last described bone. The inferior 



DEVELOPMENT OF THE UPPER EXTREMITIES. 231 

extremity is semicircular, thin, and flattened, its margin being very- 
rough, and somewhat expanded. The posterior face of the body is 
convex, and the anterior flat. 

The phalanges of the middle finger (Impudicus) are larger and 
longer than the others. The phalanges of the fore finger (Indicator) 
are next in size, but not in length, as the ring finger is rather longer 
than it. The phalanges of the ring finger (Annularis) are next in 
size, and those of the little finger (Auricularis) the smallest and 
shortest of any. 

The thumb (Pollex) having but two phalanges, the first corre- 
sponds sufficiently in its general form with the first one of the fingers : 
it may be distinguished, however, by its shortness and additional 
size. The second phalanx of the thumb, corresponding with the 
third of the fingers, is only to be distinguished by its additional bulk 
and length. 

All the metacarpal and phalangial bones have condensed lamel- 
lated structure externally, and a cancellated one internally : and, 
like other bones, are more compact in their bodies than at their 
extremities. 

There are two small hemispherical bones, called sesamoid, placed 
upon the trochlea, at the lower extremity of the metacarpal bone 
of the thumb. They answer the purposes of patellse, and facilitate 
the action of the short flexor muscle. The metacarpal bones of 
some of the fingers are, in robust individuals, occasionally furnished 
in the same way. 



SECT. V. OF THE DEVELOPMENT OF THE UPPER EXTRE- 
MITIES. 

At birth the upper extremities are larger in proportion to the low T er 
than they are at any subsequent period of life, owing, perhaps, to 
the umbilical arteries, which carry off to the placenta of the mother 
the greater part of the blood which afterwards goes to the lower 
extremities. The nearer a fcetus may be to the embryo state, the 
more marked is this relative size of the extremities, which becomes 
gradually less obvious till the age of puberty, when it almost en- 
tirely disappears. 

At birth, the ends of the clavicles are, in consequence of their 



232 SKELETON. 

advanced ossification, much less cartilaginous than those of the 
other cylindrical bones. Its shape, also, approaches nearly to that 
of the adult state. 

The scapula is also in an advanced stage of ossification, and 
large. The glenoid cavity, though still cartilaginous, is well sus- 
tained by a bony basement coining from the central point of ossifi- 
cation of the scapula, and is much farther ossified than the aceta- 
bulum. The acromion, the coracoid process, and the angles, are 
still cartilaginous. 

The os humeri is cartilaginous at both extremities, which are 
also larger, proportionally, in consequence of this state. Its infe- 
rior extremity is remarkable for the size of that portion of it which 
articulates with the radius. 

In the fore arm, the extremities of its bones are cartilaginous. The 
ulna has the olecranon large, while its coronoid process is compa- 
ratively small ; the greater sigmoid cavity is, consequently, not so 
concave as in the adult. The position of the radius, at its upper 
end, is somewhat peculiar, for it is much more anterior than in the 
adult ; a circumstance depending upon the greater size of the little 
head of the humerus, upon which it rests. This arrangement renders 
pronation more extended in the fcetus, as the radius always crosses 
the ulna with additional facility, by being placed more anterior to it. 
This fact is strongly exemplified in the bones of the fore extremity of 
animals. Bichat observes, that this greater extent of pronation ex- 
poses the annular ligament to being stretched considerably behind, 
and, consequently, the radius to luxations at its head: an accident 
by no means unfrequent among children. The late Dr. Physick 
says, that he has often seen it in consequence of nurses incautiously 
seizing them by the fore arm to help them over gutters, or to render 
them other assistance. It happens while the arm is in a state of 
pronation ; for the weight of the body, by hanging from it, increases 
the position, distends the ligaments, and produces luxation. As the 
bones of the fore arm in the fcetus are nearly straight, the interosseal 
space decreases gradually from above downwards. 

The carpus is entirely cartilaginous at birth, and consists in the 
same number of pieces that it does in the adult. Its articular cavities 
are well formed. Its size is proportionate to what it is in the adult: 
in this respect it differs from the cartilaginous extremities of the round 
bones, which are always larger from being in this state. The carpus, 
therefore, appears small, in the fcetus. 



MECHANISM OF THE UPPER EXTREMITIES. 233 

The metacarpus is cartilaginous at its extremities, but ossified in 
the middle. The phalanges are in the same state. 



SECT. VI. — OF THE MECHANISM OF THE UPPER EXTRE- 
MITIES. 

• 

The scapula and clavicle are for the superior extremity what the 
os innominatum is for the inferior ; in consequence of which, some 
anatomists consider them as a part of the trunk of the body. Though 
the convenience of anatomical description generally requires them to 
be associated with the upper extremity, I shall depart from the rule 
on the present occasion, and view them only as the basis of the 
attachments and motions of the os humeri, and of the remaining parts 
of the superior extremity. 

The upper extremities, considering them as commencing with the 
os humeri, differ materially in their position from the lower. They 
are placed much farther behind ; of which one may be satisfied fully 
by drawing a line from the middle of the glenoid cavity, to the 
middle of the acetabulum of the same side ; the body being perfectly 
erect at the time, the line will be found oblique. The advantage of 
this arrangement is to give greater latitude of motion to the upper 
extremity than if it had been placed more in front. Another im- 
portant benefit is, that by the bulk of the shoulder being placed 
behind the centre of gravity, the erect position is more easily pre-, 
served ; a different position of it, by throwing its weight forwards, 
would have had a continual tendency to produce falls, and to effect 
somewhat, in man, the same inconvenience which is felt by the 
quadruped in the erect position. Another point, also of some interest 
in tlie position of the upper extremities, is the distance to which they 
are separated from each other by the lateral projection of the scapulas, 
and, consequently, of the glenoid cavities. A distance owing to the 
length of the clavicles, and which considerably exceeds the distance 
between the heads of the ossa femorum. 

When the whole length of the superior is compared with that of 
the inferior extremities, the difference is not so great as one may 
suppose. The former is ascertained by a line drawn from the head 
of the os humeri to the end of the middle finger: as the hand is 
parallel with the bones of the fore arm, its length is also included,, 
which amounts to a considerable portion of the whole. On the con-v 

20* 



234 



SKELETON. 



trary, from the foot being articulated at right angles with the leg, 
only its thickness contributes to the length of the lower extremity. 
As far, however, as individual bones are concerned, those of the 
upper extremity, with the exception of its phalanges, are uniformly 
shorter than the corresponding bones of the lower extremity. The 
os humeri is much shorter than the os femoris — the bones of the fore 
arm than the bones of the leg — the carpal and metacarpal bones than 
the tarsal and metatarsal. 

The bones of the upper extremity are much less robust than those 
of the lower, a very certain indication of the difference of the uses 
for which they were intended. Their articular surfaces are arranged 
for great variety and extent of motion, in the seizing and handling 
of bodies; whereas in the lower extremity, they are fashioned so as 
to suit the comparatively limited number of motions requisite to pro- 
gression, and to sustain the body firmly in the upright position. 
The carpus and metacarpus are much smaller than the tarsus, and 
the metatarsus, because the latter are intended to support a great 
weight. On the contrary the phalanges of the fingers are much better 
developed than the phalanges of the toes, because the latter are not 
destined to hold bodies and to examine them, and may be dispensed 
with both in standing and in progression. 

The motions of the upper extremity are immensely varied, and 
by a short attention to them, some usefid hints may be obtained in 
regard to dislocations. 



SECT. VII. — OF THE MOTIONS OF THE SHOULDER. 

The clavicle performs a very important office in the actions of the 
shoulder, by preserving it in a fit attitude for the motions of the up- 
per extremity. The simple movements of the clavicle, of which the 
sterno-clavicular articulation is the centre, are those of elevation, 
depression, advancing, and retreating, and a rapid succession of 
these produces circumduction. The weight of the shoulder is also 
sustained by the clavicle, by the latter being fastened at the extremi- 
ty next to the sternum, and having in the cartilage of the first rib a 
fulcrum, intermediate to this attachment and to the weight at it§ 
other end. This is proved conclusively by its fracture ; for in that 
case the shoulder invariably falls down, from the lever being broken 
which kept it up. 



MECHANISM OF THE UPPER EXTREMITIES. 235 

The clavicle, also, by keeping the glenoid cavity at a distance from 
the side of the thorax, and directed outwards, gives great facility and 
latitude to certain motions in the human subject ; and which are per- 
formed with difficulty, and very imperfectly, in animals not having a 
clavicle. A principal one of these motions is circumduction, mani- 
fested by the elbow being turned inwards or outwards, and in most 
persons extends to three-fourths or even an entire circle. This 
motion concurs in the action which brings the hand to the mouth, 
in consequence of which such an action is performed with difficulty 
when the clavicle is broken. After an accident of the kind, the 
head, instead of remaining stationary as usual, is advanced towards 
the hand, without which the act cannot be accomplished. A certain 
length in the clavicle seems indispensable to the vigorous and per- 
fect action of the shoulder in particular movements ; if the clavicle 
be disproportionately long, as in females, these movements are exe- 
cuted with inevitable awkwardness and imbecility ; as, for example, 
in throwing a stone. 

The scapula presents a moveable basis, on which the motions of 
the arm are accomplished. Its primary motions are such as have 
been assigned to the clavicle, in consequence of the connexion be- 
tween these bones ; besides which, in all the extreme motions of the 
humerus, backwards or forwards, the scapula is caused to perform 
a partial rotation, the axis of which is indicated by a line drawn 
from the end of the acromion to the inferior angle. When the arm 
is brought very far forwards, the inferior angle of the scapula is 
carried outwards, and somewhat elevated, while the superior angle 
is directed towards the spine, and somewhat depressed. But when 
the arm is carried very far backwards, the inferior angle is directed 
towards the spine, and the superior angle looks forwards and up- 
wards. The clavicle in these cases moves inconsiderably, as the 
scapula enjoys a pendulous motion, and its point of suspension is the 
outer end of the clavicle ; at which place the oblong articular sur- 
faces slide laterally upon each other and decussate. The extreme 
degrees of these motions tend to dislocate this articulation, but the 
accident is prevented by the strong coraco-clavicular ligament, 
which, by its peculiar position and confirmation, resists firmly at a 
certain point. In the abduction and adduction of the arm, the 
scapula is motionless. 



236 



SKELETON. 



SECT. VIII. — OF THE MOTIONS OF THE SHOULDER JOINT. 

The os humeri is susceptible of elevation, depression, advancing, 
retreating, circumduction, and rotation. 

In elevation, the head of the os humeri slides downwards in the 
glenoid cavity, and distends the lower part of the capsular ligament. 
In this motion the scapula is apt to follow it; in which case there 
will be a less degree of distention in the capsular ligament. If the 
os humeri be carried forwards, its elevation is performed with much 
more ease, from the readiness with which the scapula follows it; 
but if it be carried backwards, this facility is much diminished. 
It is in the latter position, therefore, that dislocations downwards 
are most disposed to occur when violence is offered to the joint. 
If in every case the scapula could follow the motions of the os humeri, 
so as to present fairly its glenoid cavity, luxations would be com- 
paratively rare ; but generally the violence offered transmits its 
momentum so speedily to the joint, that the muscles of the scapula 
are taken by surprise, and have not time to adjust properly the 
glenoid cavity. 

In the depression of the os humeri, the parts constituting the 
shoulder joint are in their most natural and easy position. The 
capsular ligament becomes very loose below, and is somewhat 
stretched above. Any degree of force which might be applied to 
the member, is warded off and its direction changed by the inter- 
vention of the trunk of the body. Should, however, the force be 
applied directly in the axis of the bone, the projection of the acro- 
mion process, and the strength of the triangular ligament of the 
scapula, would arrest the dislocation. 

When the os humeri is advanced, the posterior part of the cap- 
sular ligament is put upon the stretch; but the form and arrange- 
ment of the articular surfaces are somewhat favourable to this posi- 
tion, and accordingly it is one of but little inconvenience. When the 
os humeri is retracted, its head, by being directed forwards, exer- 
cises considerable force upon the fore part of the capsular ligament, 
and when assisted by an external momentum is disposed to disloca- 
tion, forwards and inwards. 

The motion of circumduction is very extensive in the shoulder 
joint; and by it the os humeri describes a cone, of which the gle- 
noid cavity is the apex. It is a regular succession of the move- 



MOTIONS OF THE FORE ARM. 237 

ments already mentioned, and in consequence of all the motions 
forwards of the os humeri being more easy and natural, the axis 
of the cone, instead of being directly outwards, is somewhat for- 
wards. 

By rotation, is meant the revolving of the os humeri upon itself. 
The centre of this movement is not the axis of the bone, but is re- 
moved to one side of it, by the lateral projection of the head. The 
neck, however, is too short and thick to permit any great extent 
to this motion; it, accordingly, is limited in such a way as never 
to amount to luxation. Its greatest extent, in most persons, does 
not exceed the describing of half a circle, which may be ascer- 
tained by applying a finger upon the internal condyle of the os 
humeri. By it the capsular ligament is rendered, alternately, loose 
and tense on its front and back parts. Bichat observes, that in 
the anchylosis of the elbow joint, this motion, by habit, is much 
augmented, so as to supply the want of rotation of the head of the 
radius upon the ulna. The scapula and the clavicle do not vary 
their position in rotation. 



SECT. IX. OF THE MOTIONS OF THE FORE ARM. 

There are two kinds of motion in the fore arm. In the one, the 
fore arm is flexed, and extended upon the arm ; and in the other, the 
radius only changes its position in regard to the ulna. 

1. The ulna is the essential agent of the first, in consequence of 
its manner of articulation with the os humeri; the radius is only 
accessory, and is drawn by the ulna into a participation in its mo- 
tions. These two bones, it will be recollected, are disposed of in an 
inverse manner, the larger part of the ulna being above, while the 
larger part of the radius is below. This arrangement causes the 
ulna to present the principal articular surface for union with the os 
humeri, while the radius affords the principal surface to the carpus ; 
it also gives to the whole fore arm a great uniformity in its transverse 
diameter. The fore arm executes, upon the arm, flexion, extension, 
and lateral inclination. 

Where the flexion is complete, the coronoid process is received 
into its cavity, on the front of the os humeri ; and the olecranon, 
having left its cavity, is placed below the condyles. In this state 
the capsular ligament is stretched at its posterior part, while the an- 



238 



SKELETON. 



terior is thrown into folds, and is relaxed along with the lateral liga- 
ments. In the demi-flexion of the arm, there is a more equal degree 
of tension of the several ligaments. When the os humeri is reposing 
in its most easy attitude, at the side of the body, if the fore arm be 
flexed its line of motion directs the hand towards the mouth ; a cir- 
cumstance which is accounted for by the peculiar obliquity of the 
trochlea, on the lower part of the os humeri, upon which the ulna 
revolves ; and is independent of any special act of volition. It is 
said that man, above all other animals, has the mechanism of the 
upper extremity most particularly addressed to the latter motion, to 
the perfection of which the clavicle is indispensable. It is in con- 
sequence of this application of the clavicle, that if it be broken, man 
like animals which are entirely deprived of it, will in the flexions of 
the fore arm, more easily carry the hand to the opposite shoulder 
than to the mouth. 

In the full extension of the fore arm, the olecranon process being 
received into its cavity, is much above the condyles of the os humeri. 
The lateral ligaments, as well as that part of the capsule on the front 
of the joint, are in a state of tension. When the extremity is in this 
position, a fall upon the hand may produce a dislocation backwards. 
In this case the fore arm being fixed, the coronoid process affords 
the surface upon which the principal momentum of the fall is felt. 
If the ligaments on the front of the joint be not strong enough to 
withstand the force, they are lacerated, and the articular surfaces, 
passing each other, the upper parts of the ulna and radius are 
driven behind the os humeri. Bichat asse/ts, that nothing is more 
easy than to produce such a luxation on the dead body by a similar 
proceeding, and that he has repeatedly done it — that it is about as 
easy to produce this dislocation, as it is difficult to effect one at the 
scapulo-humeral articulation. In a moderate extension of the fore 
arm, produced by a small weight suspended on the hand at arm's 
length, there is a well-marked pressure of the inferior extremity of 
the os humeri against the ligaments in front of the articulation, 
which is augmented by a tendency of the ulna to describe the arc of 
a circle, from above downwards, and to separate itself from the os 
humeri. In this case the muscles which flex the fore arm are kept 
so much in the line in which they contract, or are so little removed 
from the axis of their own motion, that they contribute but little to 
sustain the fore arm in situ ; the weight is, therefore, actually sus- 
tained by the ligaments in front of the articulation. But they being 



MOTIONS OF THE FORE ARM. 239 

pressed and drawn in the manner mentioned, such great pain and 
weariness are produced as to render a continued suspension of the 
weight insupportable, the experimenter is, therefore, in a short time, 
under the necessity either of casting off the weight or of giving such 
a degree of flexion to the fore arm as will allow the muscles to con- 
tract more advantageously. 

Besides flexion and extension, the ulna has a sort of rocking mo- 
tion when the fore arm is only half bent ; but when the latter is at 
either extreme of the former positions, this motion is imperceptible, 
owing to the nature of the articular surfaces and the resistance of the 
ligaments. 

2. In the rotations of the radius upon the ulna, the latter is almost 
motionless, excepting the case specified in the last paragraph. The 
position of the radius on a plain somewhat anterior to the ulna, its 
small cylindrical upper extremity, and its broad lower one, all con- 
cur in facilitating rotations forwards and backwards. It is owing to 
the hand following these motions that the first is expressed by the 
term pronation, in which the palm of the hand is directed downwards; 
and the second, supination, in which the palm is upwards and the 
back of the hand downwards. 

Pronation is the most common, and, consequently, the easiest po- 
sition to the fore arm, when not carried to an extreme: it is adopted 
involuntarily, simply by the action of the ligaments and the particular 
shape of the articulating surfaces of the bones. It is the posture 
most generally suited to the examination and grasping of surround- 
ing bodies. In order that it may be accomplished fully, the superior 
extremity of the radius rolls on its own axis, in the loop formed by 
the annular ligament and the lesser sigmoid cavity of the idna ; while 
the lower extremity revolves around the little head of the ulna below. 
The middle part of the radius crosses that of the ulna, and the inter- 
osseous space is diminished. An excess of this motion will produce 
luxation either above or below, but more easily at the latter place ; 
both on account of the greater extent of motion there, and of the 
comparative weakness of the ligaments. 

In supination, a movement the reverse of what is described, takes 
place ; the radius revolves outwardly, and is brought parallel w T ith 
the ulna. If by any force it be carried beyond this line, a disloca- 
tion may occur, in which the little head of the ulna, abandoning the 



240 SKELETON. 

sigmoid cavity of the radius, will be thrown in front of it. An acci- 
dent, however, said to be very unusual. 

Bichat considers the cartilage between the ulna and the cunei- 
forme as a principal obstacle to these luxations ; but when it is in- 
sulated or separated from the cartilage of the radius, as sometimes 
occurs, the joint is very much weakened thereby, and more ex- 
posed to dislocations. 



SECT. X. — OF THE MOTIONS OP THE HAND. 

The hand, as a whole, performs upon the fore arm, flexion, ex- 
tension, lateral inclination, and circumduction. As it only follows 
the motion of the radius in pronation and supination, and does not 
contribute in the slightest degree to either, its appropriate motions 
can all be performed independently of them. 

In flexion the convex head, formed by the first range of carpal 
bones, slides from before backwards in the concavity which re- 
ceives it. The posterior part of the capsular ligament is stretched, 
and the anterior thrown into folds, while the lateral ligaments re- 
main at their ease. In extension, with the exception of the lateral 
ligaments, the phenomena are reversed. This extension, as is well 
known, not only brings the hand into the same line with the bones 
of the fore arm, but carries it beyond that line till it forms almost 
a right angle with it. The wrist joint, in this respect, differs from 
the other ginglymous articulations; but what it gains in extension 
it loses in flexion, as it cannot be bent so much as either the elbow 
or knee. The arrangement, however, gives great facility to the use 
of the hand. 

In the lateral inclinations of the hand, the capsule in front of and 
behind the wrist, is but little affected, but the lateral ligaments are 
alternately relaxed and tightened. As the articular surfaces are 
extensive in the line of these motions, dislocations in the direction 
of either of them are very uncommon, and when they do occur they 
are for the most part incomplete. 

Circumduction is produced by a regular succession of the motions 
described ; it, therefore, does not require a specific notice. 

Of the Partial Motions of the Hand. — Well marked changes of 
position occur between the first and second rows of the carpus ; 



MOTIONS OF THE HAND. 241 

these are principally flexion and extension. Lateral inclination or 
abduction and adduction are extremely limited, and circumduction 
does not exist. The motions, such as they are, are confined within 
much narrower limits than those of the radio-carpal articulation, and 
have for their main fulcrum the head of the magnum. 

The lateral articular surfaces of the several bones of the carpus, 
though they present the arrangement of joints, have not an appre- 
ciable motion upon each other. Whatever changes of position 
happen among them, are probably so obscure that they never ap- 
pear, except under the influence of great and sudden violence. 
The complexity of the mechanism of the wrist, seems to have a 
double object in view: for ordinary circumstances of impulse and 
motion, the flexion and extension of the first row upon the second, 
as a whole, is sufficient ; but when a great momentum is commu- 
nicated to the structure, the number of pieces which form it, and the 
variety of their shapes and mode of attachment, diffuse the violence 
throughout the whole wrist, and generally save it from dislocation 
or fracture. The fracture of a single bone, excepting from gun-shot 
wounds, is a very unusual circumstance : I have had, however, in pos- 
session a scaphoides which was broken through transversely, and 
had probably been in that state for a long time ; as all appearance 
of inflammation, at the period of my finding it, was absent ; and as 
the fractured surfaces had become highly polished by rubbing against 
one another. 

The pisiform bone moves with much freedom inwardly and out- 
wardly on the cuneiform, but its motion up and down is resisted by 
the muscles which are attached to it. Owing to its articular cavity 
being insulated, and to its own remoteness, a dislocation of it, if it 
did occur, would interfere but little with the general uses of the 
hand. 

The. metacarpal bone of the thumb has a very free motion on the 
trapezium, in flexion, extension, adduction, abduction: and circum- 
duction as the result of the other four. In consequence of this variety 
of movement in it ; of its position on a plane anterior to that of the 
fingers ; and of a corresponding obliquity of the trapezium, the fnumb 
can, in all cases of grasping and examining bodies, antagonize the 
finders. The circumduction of the thumb resembles very much that 
of the wrist, or shoulder joint, though the mechanism of the articular 
surfaces is different. In this motion, it describes a cone or circle, 

Vol. I.— 21 



242 SKELETON. 

the anterior segment of which is larger, and performed with more 
facility than the posterior. 

The second and third metacarpal bones are so closely bound to 
the carpus, that their motion above is almost imperceptible ; in con- 
sequence of their length, the motion is more appreciable below, but 
even there it is very much restricted. The fourth metacarpal bone 
has a limited ginglymous movement, which is sufficiently demon- 
strable, and the fifth has it in a considerable degree ; it also admits 
of a sort of adduction, by which it is brought nearer to the other 
bone. 

The first phalanges admit of flexion, extension, adduction, ab- 
duction ; and circumduction, by the successive performance of the 
others. The first phalanx of the thumb has the three last motions 
very much curtailed, in consequence of the necessity of great strength 
and stability in this joint, so as to antagonize firmly the fingers. The 
remaining phalanges perform, simply, flexion and extension. The 
latter, as in the knee and elbow, rarely goes beyond the axis of the 
limb, whereas the former, from the extent of the articular surfaces 
and the particular mechanism of the joint, permits the hand to be 
closed and doubled. 

From what has been said, it will not be difficult to form a general 
conception of the great variety of motions resulting from the number 
and arrangement of the pieces constituting the upper extremity. 
The os humeri being the basis of them, may be presented in any 
direction ; the bones of the fore arm may be alternately retracted or 
protruded, and by the revolving of the radius, will permit the palm 
of the hand to apply itself at any point ; and, again, the multiplicity 
of simple motions of the hand, and the exhaustless variety of their 
compounds, contribute to give to the upper extremity, in man, a 
perfection of mechanism infinitely beyond any thing which can be 
devised by the powers of art : a sentiment cogently expressed by 
the late Professor Wistar: who remarked, that "The human hand, 
directed by the human mind, is the most perfect instrument that man 
ever saw or ever will see." 



THIGH BONE. 243 

CHAPTER VI. 

Of the Inferior Extremities. 

The bones of the inferior extremities are the os femoris, the tibia, 
fibula, patella, and a large number which enter into the composition 
of the foot. 

sect. i. — of the thigh bone, — (Os Femoris, Femur.*) 

This is the only bone in the thigh, and extends from the trunk 
to the leg. It is considerably the longest and largest bone in the 
skeleton, and presents a conformation entirely peculiar. For the 
purposes of description, it is divided into the two extremities and 
the body. 

.The superior or iliac extremity presents three well marked emi- 
nences, the head, the great and the little trochanter. The head is 
the articular surface above, and forms rather more than one-half of 
a perfect sphere. Its smoothness indicates the existence of a car- 
tilaginous crust on it during life, and is only interrupted by a small 
pit a little below its centre, which gives attachment to the round 
ligament of the hip joint. Its articular surface is more extensive 
above than below, as that part is chiefly employed in sustaining the 
trunk, and comes in contact with a corresponding surface of the os 
innominatum. The head is supported on a branch of the os femoris 
called the neck, which, projecting from the internal face of the bone 
between the trochanters, is directed inwards and upwards at an angle 
of about thirty-five degrees, but varying in different subjects. The 
neck is two inches in length, oval, or resembling a flattened cone, 
the greater diameter of which is vertical ; and arises by an extensive 
base along the upper end of the os femoris. It has a great multitude 
of foramina dispersed over it, which penetrate to its interior, and 
give passage to blood vessels; the largest of them are on its poste- 
rior surface. Some of these foramina are also occupied by fibres. 

* Anat. Atlas, Figs. 80, 81. 



244 SKELETON. 

A superficial horizontal fossa, formed by the tendon of the obturator 
externus, may be seen crossing the posterior face of the base of the 
neck. 

The great trochanter is situated at the superior part of the base 
of the neck, and though presenting a well marked, elevated summit, 
rising straight upwards, does not reach the altitude of the head, but 
falls short of it half an inch. The trochanter major rests upon a 
broad base, has its surface much diversified, is somewhat prominent 
in front and externally ; but presents on the side which is next to the 
head of the bone a deep rough concavity, which is occupied by the 
insertion of the small rotatory muscles on the back of the pelvis. 
On its summit is a small smooth spot, marked by the insertion of the 
pyriformis muscle ; below this, and also externally, is a broad sur- 
face, slightly convex, into which the gluteus medius is inserted; 
below this, again, is a second prominent and rounded surface, over 
which a part of the tendon of the gluteus magnus plays. On the 
front of the trochanter, and just in advance of the insertion of the 
gluteus medius, is an oblong surface, proceeding obliquely down- 
wards and outwards, into which is inserted the gluteus minimus. 

The trochanter minor is much smaller than the other, and is a 
conical process, placed on the internal posterior face of the bone, 
at the lower end of the root of the neck. It receives the common 
tendon of the iliacus internus and psoas magnus muscles. A broad 
elevated ridge joins the two trochanters on the posterior face of the 
bone, and into its middle half is inserted the quadratus femoris 
muscle. A much smaller ridge, and by no means so elevated, runs 
in front, from the one process to the other, and indicates the line of 
attachment of the capsular ligament of the hip joint. 

The inferior extremity of the os femoris is much more volumi- 
nous than the superior, and is divided into two parts, called the 
internal and the external condyle. These condyles are of very 
nearly the same size, but, being separated by a notch behind, they 
are placed somewhat obliquely in regard to each other; and the 
internal, from being the most oblique, and, consequently, the most 
protuberant, also seems to be the larger. If the os femoris be 
placed exactly vertical, the internal condyle has the appearance of 
being the longest ; but, if it be placed in its natural obliquity, t&e? 



THIGH BONE. 245 

lower face of the condyles is on the same plane. In front, the con- 
dyles unite to form an articular trochlea, on which the patella plays: 
this trochlea is unequally divided by a vertical depression, so as to 
have its more extensive surface external. This latter surface is the 
anterior part of the external condyle, and is much more elevated 
than the internal part of the trochlea, which belongs to the internal 
condyle. Posteriorly, the internal condyle projects more than the 
external, and both have the articular surfaces, there, so much elon- 
gated backwards and upwards, as to admit of a very great flexion, 
of the leg. 

Each condyle presents an internal and an external face. The 
internal condyle has on its internal face a tuberosity, from which 
proceeds the internal lateral ligament of the knee; on its external 
face it forms one-half of the notch which separates it from the other 
condyle, and at its anterior part in the notch may be observed a 
small depression, from which proceeds the posterior or internal 
crucial ligament. The external condyle, also, has on its external 
face a tuberosity, from which proceeds the external lateral ligament 
of the knee, and just below it a depression for the origin of the 
popliteus muscle. Its internal face forms the other half of the notch 
just mentioned, and on the posterior part of this face is a small 
depression for the attachment of the anterior or external crucial 
ligament. The inferior face of the condyles is somewhat flattened, 
the transverse diameter of that of the external being rather longer 
than the other. The inferior extremity of the os femoris is beset 
with foramina, large and small, for the passage of vessels and the. 
attachment of fibres. 

The body of the os femoris begins with the trochanters, and ter- 
minates in the condyles. It is slightly bent, so as to present the 
convexity of the curve forwards. Its size is gradually diminished 
to the middle; it then begins to enlarge, and continues to augment 
till it terminates in the large inferior extremity. The body is very 
nearly round, and departs from that figure only on its posterior face, 
where an elevated rough ridge is found, occupying the superior 
two-thirds of the bone, and called the linea aspera. The linea 
aspera begins broad, rough, and flat, on a level with the trochanter 
minor; it narrows as it descends, and becomes, at the same time, 
more elevated. In the whole course of the linea aspera, an internal 
and an external margin are very obvious. Its lower extremity 

21* 



246 SKELETON. 

bifurcates into two superficial, slightly marked ridges, one on each 
side, which may be traced into the posterior extremity of its cor- 
responding condyle. Between these ridges the surface of the bone 
is flattened. The superior half of the external margin of the linea 
aspera is occupied by the insertion of the gluteus magnus, and the 
remainder by the origin of the biceps flexor cruris. This margin 
also gives origin to the vastus externus. The internal margin of 
the linea aspera is mostly occupied by the insertion of the triceps 
adductor, and by the origin of the vastus internus. 

In the linea aspera, near the middle of the bone, is Ihe canal for 
the nutritious artery, which slants upwards : occasionally one or 
more canals, besides, are found in it for the same purpose. 

The texture of the os femoris is compact in its body. Its extre- 
mities are cellular, with the exception of a thin lamina forming 
their periphery : the cylindrical cavity in its middle, like that in all 
the other long bones, is reticulated. The ossa femorum approach 
each other very closely at their inferior extremities, but are widely 
separated at their superior, in consequence of the length of their 
necks, and of the distance of the acetabula from one another. 



SECT. II. — OF THE LEG.* 

Two bones form the leg, the tibia and the fibula, to which may 
be added the patella, from its attachment to the tibia. 



Of the Tibia, (Tibia.) 

The tibia is placed at the internal side of the leg, and extends 
from the thigh to the foot. After the os femoris, it is the longest 
and the largest bone in the skeleton. It is divided into the body 
and the two extremities. 

The superior extremity of the tibia is oval, transversely, and pre- 
sents an extent of surface suited to the articular face of the two con- 
dyles of the os femoris, to which it is joined. It has here two su- 
perficial cavities for receiving the ends of the condyles; one of them 

* Anat. Atlas, Figs. 82, 83, 84, 85. 



THE LEG. 247 

is internal and the other external. The internal is the deeper and 
more extensive of the two, and, being oval, has its long diameter 
in an antero-posterior direction. The external, besides being 
smaller and more superficial, is more circular; and, from the want 
of elevation in its margins, scarcely presents at all the appearance 
of a cavity. These two cavities, which approach to within half 
an inch of each other, are kept entirely separated by an elevated 
triangular ridge, with a broad base, called the spinous process of 
the tibia. The summit of the ridge presents two tubercles, one at 
each end, separated by a pit, which serves to attach the posterior 
end of the external semi-lunar cartilage. The ridge is placed nearer 
the posterior than the anterior" margin of the tibia. Its base, in front 
is depressed for the attachment of the anterior crucial ligament, and 
just before this is a rough, triangular sp?,ce, extending to the anterior 
margin of the bone, and covered by fat in the recent subject. Be- 
tween the ridge and the posterior margin of the bone is a deep de- 
pression for the attachment of the posterior crucial ligament. 

The circumference of the superior part of the tibia, just below its 
articular surface, is flat before, somewhat flat and concave behind, 
and bulging at the sides. The flatness, in front, is triangular, having 
its base upwards and the apex downwards, the latter terminates in 
a well marked, broad, rough rising, which is the tubercle of the 
tibia, and serves for the insertion of the tendon of the patella. The 
concavity behind is made by the popliteus muscle, and slopes from 
above obliquely inwards and downwards. The projection is great 
on the internal side of the upper extremity of the tibia, and at its 
posterior part has a depression made by the insertion of the semi- 
membranosus tendon. The external projection is thicker in front 
than behind; at the latter point it has a small articular face, looking 
downwards, for the head of the fibula. 

The inferior extremity of the tibia is much smaller than the supe- 
rior. It is terminated by a transverse quadrilateral cylindrical con- 
cavity, by which it articulates with the astragalus. This concavity 
is narrower and deeper internally, than externally, and is traversed 
from before backwards by a low broad ridge. It is bounded inter- 
nally by the internal malleolus, a large process of half an inch in 
length, the external side of which is a continuous surface with the 
cylindrical concavity, and forms part of the joint. The«other side 



248 SKELETON. 

of the malleolus is superficial, being just beneath the skin. A shallow 
groove exists in its posterior part, which transmits the tendon of 
the tibialis posticus and of the flexor longus digitorum pedis. In- 
feriorly, the malleolus is notched, or presents a depression, for the 
origin of the internal lateral ligament-, and just before the depression 
it is elongated into a point. The lower end of the tibia presents, 
before and behind a slight swell, running transversely just above the 
articular surface. The posterior swell is occasionally slightly marked 
by the tendon of the flexor longus pollicis pedis. 

Externally, the circumference of the lower end of the tibia pre- 
sents, longitudinally, a concavity which is in contact with the lower 
end of the fibula. This concavity terminates insensibly above, but 
is deep below, where it is bounded before and behind by an elevated 
point of bone, of which the posterior is the highest. The concavity 
is placed nearly in the vertical line of the little articular face for the 
fibula, on the head of the tibia ; and at its lower margin, there is 
frequently a small lunated surface, which is continuous with the ar- 
ticular surface for the astragalus, and is consequently a part of the 
cavity of the ankle joint. Just above this lunated surface the bone 
is rough for the origin of short ligamentous fibres, which unite it to 
the fibula. 

The body of the tibia commences just below the enlarged upper 
extremity, and terminates near the ankle. In the front view of it, 
it diminishes continually in descending, in its superior two-thirds : 
afterwards it enlarges gradually to the lower extremity ; in the lateral 
view it diminishes downwards almost to the lower extremity. It is 
slightly bent forwards, and is generally prismatic, more particularly 
above ; one of its faces is internal, another external, and the third pos- 
terior. The internal face is rounded, and, with the -exception of its 
upper part, where the flexor tendons are inserted, it is only covered 
by the skin. Its external face is flat, excepting below, where it is 
rounded and is covered by the muscles on the front of the leg. The 
posterior face is slightly rounded, except at its upper part where it 
is crossed by a line running obliquely from the articular surface for 
the fibula, downwards and inwards: above which line, is the super- 
ficial triangular depression for the popliteus muscle. 

The thjpe sides of the tibia are marked off from each other by 



THE LEG. 249 

ridges of bone. The anterior ridge, called the spine or crest, begins 
at the external margin of the tubercle for the insertion of the tendon 
of the patella, and may be traced very distinctly, in the form of an 
S very slightly curved, almost to the malleolus internus : it is more 
elevated in its middle. The external ridge is a straight line running 
from one extremity of the bone to the other ; to it is attached one 
edge of the interosseous ligament. The internal ridge is rounded, 
but also runs the whole length of the body of the bone, being more 
distinct below. The internal lateral ligament of the knee and the 
soleus muscle are attached to it, above ; and below, the flexor longus 
digitorum pedis. 

Foramina large and small, for blood vessels and fibres, are found 
on the circumference of both extremities of the tibia. On its pos- 
terior face, about one-fourth of its length from the head, is a large 
canal sloping downwards, through which passes the nutritious 
artery. Its structure, like that of the other long bones, is cellular 
at its extremities ; but compact in the body, where it presents a 
cavity occupied by cancellated matter. It will now be understood 
how it articulates with the fibula, externally, at both ends ; with the 
os femoris above ; and with the astragalus below. 



Of the Fibula , (Perone.) 

The fibula is placed at the external side of the tibia, and extends 
from the head of the latter to the foot : it is much smaller, and not 
quite so long as the tibia, and is so articulated with it as to be on 
a line with its posterior face. It is to be studied in -its two extre- 
mities and in its body. 

The upper extremity of the fibula is considerably enlarged and 
irregular. It presents, above, a small articular face directed up- 
wards and very slightly concave, by which it joins the correspond- 
ing face of the tibia. This surface is bounded behind by a sort of 
styloid process, into which is inserted the tendon of the biceps flexor 
cruris. The circumference of the bone, in advance of this, furnishes 
attachment to the external lateral ligament of the knee. 

The inferior extremity of the fibula is also enlarged, being flat- 



250 SKELETON. 

tened on its tibial side, but more rounded externally. This part of 
the fibula is called the malleolus externus. It descends lower than 
the internal ankle, and is also more prominent and large. Its tibial 
side presents, below, a small triangular slightly convex articulating 
surface, which reposes against the side of the astragalus ; behind, 
and somewhat below it, is a small rough depression, which, with 
the adjoining inferior margin of the bone, gives origin to the three 
fasciculi of the external lateral ligament of the ankle. Above the 
articular surface, the bone is rough and slightly rounded where it 
is received into the side of the tibia, and sends off many short liga- 
mentous fibres to it. The anterior margin of this extremity of the 
fibula is thin and projecting, the posterior surface is flat and broad, 
and is slightly scooped out into a longitudinal groove, which trans- 
mits the tendons of the two peronei muscles. The pointed termi- 
nation below, of the malleolus externus, is sometimes called the 
coronoid process. 

The body of the fibula extends between its extremities. It is 
irregularly triangular, somewhat smaller above than below, thick 
posteriorly, thin anteriorly, and slightly convex in its length be- 
hind. 

There are three faces to the fibula, one is external, another inter- 
nal, and the third posterior. The first is semi-spiral, and turned 
forwards above ; its superior third gives origin to the peroneus lon- 
gus muscle, and the middle third to the peroneus secundus: its 
lower third exhibits the semi-spiral arrangement which may be 
traced into the groove on the posterior part of the malleolus exter- 
nus, and thereby indicates the course of the tendons of these pero- 
nei muscles. The internal face is directed towards the tibia ; it is 
divided by a low longitudinal ridge into two parts, of which the 
anterior is the more narrow. The ridge itself, well marked in the 
middle two-fourths of the bone, is indistinct above and below ; and 
furnishes attachment to the interosseous ligament. The space in 
front gives origin to the extensor proprius pollicis, and the exten- 
sor communis digitorum : and the space behind gives origin to the 
tibialis posticus. The posterior face is also somewhat semi-spiral, 
its superior end being outwards, and the inferior end inwards. The 
superior third gives origin to the soleus muscle, and the remainder 
to the flexor longus pollicis pedis. 



THE LEG. 251 

The angles of the fibula which are formed by the junction of 
the three surfaces described, differ somewhat among themselves. 
The anterior angle is frequently very sharp and elevated in its 
middle half, and below it bifurcates into two ridges, including be- 
tween them a triangular space, which is only covered by the inte- 
guments. The posterior angle is well marked, and winds so as to 
be external above, and posterior near the foot. The internal angle, 
formed by the union of the internal and the posterior surfaces, is 
only very well marked in its middle half. The projection of this 
angle gives to the bone the appearance of inclining inwards to- 
wards the tibia, besides which it has actually a little bend in that 
direction. 

Near the middle of the posterior face of the fibula, a canal 
sloping downwards, conducts the nutritious artery. The circum- 
ference of the extremities, like that of the other long bones, pre- 
sents a multitude of foramina for vessels and the filaments of fibres 
to pass. It is composed in its extremities of cellular or spongy 
structure, and in its body of compact matter enclosing a cavity oc- 
cupied by cancellated structure. 



Of the Patella, (Rotule.) 

The patella is a small bone, intermediate to the thigh and to the 
leg, and placed on the fore part of the knee joint ; it is smaller in 
proportion in females than in males. 

Its anterior face is uniformly convex and rough, and is studded 
with a considerable number of foramina for the passage of vessels, 
and for the attachment of fibres. The course of the longitudinal 
fibres composing the front of the bone, is also well marked. The 
posterior face of the patella is an extensive articular surface, divided 
unequally by a broad longitudinal elevation, which runs from the 
superior to the inferior margin of the bone. The part of this surface 
external to the ridge, is the largest and the most concave, and is 
applied to the trochlea, in front of the external condyle of the os 
femoris; while the smaller surface is on the internal side of the 
ridge, and is applied to the trochlea of the internal condyle. 

The circumference of the patella is nearly oval, the long diameter 



2.V2 SKELETON. 

being transverse. Its thickness is much augmented above, where 
it presents a rough, and somewhat unequal flatness for the insertion 
of the tendon of the rectus femoris. Below, the bone is thinner, 
and elongated into a conical point, from which proceeds the tendon 
of the patella to be inserted into the tibia. Laterally, the margins 
are thinner still. 

The texture of the patella is cellular, covered by a lamina of 
condensed bony matter. It is developed in the tendon of the ex- 
tensors of the thigh, and with the exception of its posterior face 
remains in a state almost entirely cartilaginous, for a year or two 
after birth. Its base is fibrous, in which is deposited, subsequently, 
the calcarious matter. In its fracture union is effected more fre- 
quently by the fibrous base alone, than by perfect ossification. In 
order to put it into its proper position, turn the point downwards, 
and apply the greater surface behind, to the trochlea of the external 
condyle. The patella is said to be to the tibia, what the olecranon 
is to the ulna; and is, therefore, a sort of appendage to it, united 
by ligament instead of being continuous with it, as is the case 
with the olecranon. 



SECT. III. — OF THE FOOT.* 

The foot forms the third section of the inferior extremity, and is 
placed at a right angle to the bones of the leg. The size of its 
bones varies much in different individuals, depending largely upon 
their modes of life, and dress : it also t varies considerably in the two 
sexes, being, for the most part, smaller in the female. The foot is 
oblong, narrower behind than before ; presents one surface above, 
which is its back, and another below, which is the sole ; a posterior 
extremity called the heel, and an anterior extremity called the point; 
also its internal margin is much thicker, longer and more concave, 
than the external margin. 

The foot is divided into Tarsus, Metatarsus, and Toes or Pha- 
langes. 

* Anat. Atlas, Figs. 86 to 92, inclusive. 



THE FOOT. 253 



Of the Tarsus, (Tar se.) 

The tarsus forms the posterior half of the foot, and is composed 
of seven distinct bones, which are arranged on a plan, and present 
features having scarcely a single point of resemblance with the 
carpus. These bones are, the Os Calcis, the Astragalus, the Navi- 
culare, the Cuboides, the Cuneiforme Externum, Cuneiforme Me- 
dium, and Cuneiforme Internum. 



Of the Os Calcis, (Calcaneum.) 

The calcaneum, or heel bone, forms, almost exclusively, the pos* 
terior half of the tarsus, and may be readily distinguished by its 
greater magnitude. Its shape is very irregular. Its greatest dia- 
meter is in the length of the foot; it is also thicker vertically than 
transversely. 

The superior face is deeply scooped out, at its fore part, and is 
formed there into two articular surfaces, for joining with the astra- 
galus: these faces are separated from each other by a rough fossa, 
which runs from within obliquely forwards and outwards. The 
anterior external part of this fossa is deep, broad, and triangular; 
the posterior part is narrow, is occupied by a ligament, and allows 
the two articular surfaces to come nearer. Just behind the fossa is 
the first articulating surface, lying parallel with it; being oblong, 
convex, semi-cylindrical, and looking obliquely upwards and for. 
wards. Before the fossa is the second surface : it is oblong, much 
smaller than the first, and is very frequently divided into two by a 
transverse notch, and is concave. The part of the bone upon which 
this face is wrought, is called, by the French, the little apophysis. 
I have frequently remarked, that the face posterior to the first men- 
tioned fossa is smaller and more vertical in the African than in the 
European ; the os calcis, behind it, is also smaller and longer. The 
upper posterior face of the bone is somewhat concave. 

The under surface of the os calcis is slightly concave, longitudi- 
nally. It is bounded, behind, by two tuberosities, of which the in- 
ternal is larger than the external ; they both give origin to muscles 

Vol. I.— 22 



254 SKELETON. 

of the sole of the foot and to the aponeurosis plantaris. There is 
also a tuberosity bounding the same surface in front, from which 
arise the ligaments that connect this bone with the adjoining ones. 

The anterior extremity of the os calcis forms the greater apophysis, 
and is terminated in front by a triangular and slightly concave sur- 
face, by which it articulates with the os cuboides. The posterior 
extremity is convex and rough : constitutes the heel, and near its 
middle receives the tendo-achillis ; the upper part is sloping and 
more smooth, in order to accommodate this tendon in the flexions of 
the foot. 

The external surface of the os calcis is flat, with the exception of 
a gentle rising in. its middle; it is marked, occasionally, by a super- 
ficial groove, indicating the course of the tendons of the peronei 
muscles. The internal surface is very concave, and obtains the 
name of sinuosity ; along it pass the tendons of several muscles from 
the back of the leg, of which that of the flexor longus pollicis pedis 
makes a conspicuous groove on the under surface of the little apho- 
physis. 



Of the Astragalus, (UJistragale.) 

This is the next in size to the os calcis, and is placed on the su- 
perior part of the latter, between it and the bones of the leg. 

The astragalus presents, above, a semi-cylindrical surface, by 
which it is put in contact w r ith the tibia. This surface is narrower, 
and continued farther behind than it is before ; is slightly depressed, 
longitudinally, in its middle, and, consequently, presents an ele- 
vated margin on either side, of which the external is the broadest 
and highest. This articular face continues on each side of the bone, 
and is more extensive externally, where it comes in contact with the 
fibula or malleolus externus, than internally, where it touches the 
malleolus internus. 

The inferior face of the astragalus is traversed by an oblique rough 
fossa, going from within outwards and forwards, and corresponding 
in size with that on the upper face of the os calcis. Behind the 



THE FOOT. 255 

fossa, and parallel to it, is a deep oblique semi-cylindrical concavity, 
suited to the adjoining face of the os calcis ; and before the fossa is 
a narrow oblong convexity, suited to the corresponding articular 
concavity of the same bone. When the latter is divided into two 
facets, the convexity of the astragalus presents also two facets, sepa- 
rated by a small ridge. 

The anterior extremity of this bone is terminated by a convex 
head, the horizontal diameter of which is the greatest. This head 
articulates with the scaphoides, and is continuous with the surface 
that rests upon the little aphophysis of the os calcis. On the inter- 
nal side of the head is a small triangular surface, continuous with 
the others, that rests upon a strong ligament going from the os cal- 
cis to the scaphoides. Above, immediately before the surface for 
the tibia, is a small depression, which, in the flexions of the foot, 
receives the anterior margin of the articular surface of that bone. 
The posterior extremity of the astragalus is thin, and has a notch, or 
groove formed in it by the tendon of the flexor longus pollicis pedis. 



Of the JYaviculare, or Scaphoides, (Scaphoide.) 

It is situated at the internal side of the tarsus, between the astra 
galus and the cuneiform bones, and has its greatest diameter trans- 
verse. Its circumference is oval, thicker above than below, and at 
its internal side presents a large tuberosity; into which is inserted 
the tendon of the tibialis posticus. Sometimes the external margin 
has a small articular face, where it comes in contact with the cu- 
boides. 

The scaphoides, presents, behind, a deep concavity, which re- 
ceives the head of the astragalus ; anteriorly, it is somewhat convex, 
but this surface is divided by small ridges into three triangular faces, 
for the three cuneiform bones. Of these faces the internal is broader 
below than above ; the others are broader above than below. 



256 



SKELETON. 



Of the Ctcboides, (Cuboide.) 

It is situated at the external side of the tarsus, between the os 
calcis and the metatarsal bones. Its figure is irregular, but, per- 
haps, sufficiently indicated by its name. It is narrower externally 
than internally, and has the posterior extremity oblique. 

The superior face of the cuboides is rounded, but rough. The 
inferior face has in its middle a broad elevated ridge running almost 
transversely, but somewhat forwards. The external extremity of 
this ridge is marked by a trochlea, on which plays the tendon of the 
peroneus longus ; the tendon is then conducted along a groove be- 
tween the ridge and the anterior margin of the bone. 

The internal face is flat, and has in its middle a circular facet 
where it comes in contact with the cuneiform externum. The pos- 
terior face joins the os calcis, is triangular, and semi-spiral. The 
anterior face is oblong, transversely, and is divided by a slight ver- 
tical rising into two, for articulating with the last two metatarsal 
bones. 

Of the Cuneiforme Internum, , (Premier Cuneiforme.) 

It is placed at the internal anterior extremity of the tarsus, be- 
tween the scaphoides and the first metatarsal bone, and may be 
distinguished from the other cuneiforms by its greater size. Its 
thiekesfrpart is below. 

The anterior face presents a long vertical convexity which joins 
the first metatarsal bone. The posterior face is not so extensive 
and is formed into a triangular concavity, having the broadest part 
below, which joins the internal facet of the scaphoides. The in- 
ternal side is semi-cylindrical and rough; it is marked, anteriorly? 
near its middle, by the tendon of the tibialis anticus. The external 
side is somewhat concave, and generally rough, and is marked just 
below its superior margin by two articular facets, of which the an- 
terior is the smaller, and comes in contact with the second metatarsal 
bone ; the posterior, from its concave obliquity, gives a slope to the 
upper margin of the bone, and is in contact with the cuneiforme 
medium. 



THE FOOT. 257 



Of the Cuneiforme Medium, [Second Cuneiforme.) 

The middle or second cuneiform bone is placed upon the sca- 
phoides, immediately on the outside of the cuneiforme internum. 
It may be distinguished by being the smallest bone of the tarsus. 
Its iigure resembles sufficiently well a wedge ; the base of which is 
above, and the edge below. 

Its posterior face is slightly concave where it joins the scaphoides ; 
the anterior face is slightly convex, and articulates with the second 
metatarsal bone. The internal face presents, superiorly, an oblong, 
slightly convex, and oblique articular facet, which touches the cunei- 
forme internum : what remains of this side is rough, for the origin of 
ligamentous fibres. The external face is somewhat concave, and 
presents, at its posterior part, a vertical articular face for joining the 
cuneiforme externum; but, anteriorly, it is rough for the origin of 
ligamentous fibres. 

In the articulated foot the lower part of this bone is almost con- 
cealed between the other two cuneiforms. 



Of the Cuneiforme Externum, [Troisieme Cuneiforme.) 

The external or third cuneiform bone is placed upon the scaphoides, 
between the second cuneiform and* the cuboides. Of the three 
bones it is the second in size, and is also appropriately nain^d from 
its shape. The base is upwards. 

The posterior face furnishes, on its superior half to join the sca- 
phoides, a quadrangular articular facet, sloping outwardly, below 
which the bone projects into the sole of the foot. The anterior face 
is fiat, and articulates with the third metatarsal bone. The internal 
face presents, above, two articular facets, of which the one at the 
posterior end is larger than the other, and joins the second cunei- 
form ; the other, at the anterior end, is very small, and touches the 
second metatarsal bone. Below these facets the bone is rough, and 
gives origin to ligamentous matter. The external face, at the 
middle of the base forms an angular projection, behind which is a 
small oval articular surface that joins the cuboides. The remain- 

22* 



258 SKELETON. 

der of this face is rough, for the origin of the ligaments, with the 
exception of a very small articular facet at the anterior superior 
corner, which joins the fourth metatarsal bone. 



The structure of the bones of the Tarsus is uniformly cellular 
within, the cells being enclosed by a thin lamina of condensed 
matter. The astragalus is rather stronger and more compact than 
any of the others. I have seen one instance, however, in which it 
had been separated into two pieces by a transverse vertical fracture, 
going from the ankle joint to the articulation with the os calcis. 
The observation was made after it had been boiled : the callus had 
completely united the two fragments, and no displacement had oc- 
curred. 

If a vertical section of the os calcis and of the astragalus be made, 
the parietes of these cells are found to radiate from the upper articu- 
lar surfaces like columns, so as to prevent the bones from being 
crushed by the vertical weight of the body.. 



Of the Metatarsus, (Metatarse.) 

The metatarsus succeeds to the tarsus, and is formed by five long 
parallel bones like the metacarpus. They are called numerically, 
beginning on the inner side, or that of the great toe. There are 
four intervals between them, which are filled up by the interos- 
seous muscles. 



Of the First Metatarsal Bone. 

Placed at the inner side of the foot upon the cuneiforme internum, 
and forming the base of the great toe, it may be readily distinguished 
in the separated bones by its greater size and shortness. 

The posterior extremity presents an oblong articular concavity, 
the greatest length of which is vertical, for joining the cuneiforme 
internum. The internal semi-circumference of this extremity is con- 



THE FOOT. » 259 

vex, while the external is slightly concave or flat ; below, it presents 
a prominent tubercle, into which is inserted the tendon of the pero- 
neus longus. 

The anterior extremity, also called the head, is rounded and con- 
vex, forming an articular surface for the first phalanx of the great 
toe. This surface is continued far back below, and presents there, 
for the sesamoid bones, a trochlea with a longitudinal ridge in its 
middle. The lateral surfaces of the head are rough and concave, 
for the origin of the lateral ligaments. 

The body is much smaller than the extremities, and is prismatic. 
Its internal side is rounded, the external side flattened, and the in- 
ferior side concave, longitudinally, for lodging the muscles of the 
great toe. 

Of the Second Metatarsal Bone. 

This is the longest of any, and may be distinguished from the others 
principally by that circumstance. 

The posterior extremity is triangular, the broadest part being 
above. It presents a surface very slightly concave, almost flat, 
which rests upon the cuneiforme medium. The sides of this ex- 
tremity being flattened, laterally, it is locked in between the inter- 
nal and external cuneiforms ; on its internal side, above, is an arti- 
cular facet, where it comes in contact with the cuneiforme internum, 
and, externally, it has two articular facets. The posterior one of 
the latter touches the cuneiforme externum, and the anterior, which 
is smaller, comes in contact with the third metatarsal bone. These 
two facets run into each other by an angular rising. 

The anterior extremity is convex and rounded; its vertical dia- 
meter is more considerable than its transverse, and the articular face 
which it furnishes to the second toe is continued considerably below, 
in order to assist the flexion of the first phalanx. Its circumference 
is rough and flattened laterally, for the origin of the ligaments. 

The body is smaller than either of the extremities, and decreases 



260 . SKELETON. 

gradually from behind forwards. It is flattened on each side, and 
elevated longitudinally above and below, into a ridge. There is a 
curvature in its length, which makes it convex above, and concave 
below, for the lodgement of muscles. 



Of the Third Metatarsal Bone. 

This is rather shorter than the second, but has very much the 
same shape. 

Its posterior extremity, or base, is triangular, has the broadest 
part above, and articulates with the third cuneiform ; the surface for 
the latter, slopes outwardly. Its circumference is flattened laterally, 
and presents, internally, at its posterior corner, a small face, which 
articulates with the second metatarsal ; externally, it also presents, 
at its superior corner, an articular facet, which joins the fourth me- 
tatarsal. 

Its body and anterior extremity, do not present any essential 
points of difference from the second metatarsal. 



Of the Fourth Metatarsal Bone. 

It is somewhat shorter than the third, and is placed upon the in- 
ternal of the two anterior faces of the cuboides. 

The posterior extremity, or base, is more quadrangular than the 
base of the preceding bones. It presents an articular face to the 
cuboides, and which is also square or nearly so, flat, and slopes 
outwardly. On its sides it is irregular; internally, at the superior 
margin, it has two articular facets, continuous with each other, but 
forming thereby an obtuse angle ; the anterior joins the third meta- 
tarsal; and the posterior, which is much the smaller, touches the 
cuneiforme externum. Below these, the surface is rough. The 
articulation with the cuneiforme externum is occasionally deficient. 
I have observed the latter, particularly in the negro, and it seems to 
arise from the unusual development of the cuboides. The external 
surface of the base has at its superior corner an articular facet for the 



THE FOOT. 261 

fifth metatarsal bone, and below it an oblique deep fossa, before 
which is a tubercle. 

The anterior extremity and the body of this bone, though smaller 
than those of the preceding, do not present any essential points of 
difference. 

Of the Fifth Metatarsal Bone, 

This is shorter than any of the others, excepting the first, and is 
placed on the front of the cuboides, externally. 

Its base is remarkable, and distinguishes it strongly, by being pro- 
jected considerably beyond the external margin of the cuboides, and 
forming there a large tubercle, into the superior part of which is 
inserted the tendon of the peroneus tertius, and into the posterior 
part, the tendon of the peroneus secundus. The base, also, has a 
triangular flat surface, sloping considerably outwards, which articu- 
lates with the cuboides. On the internal side is the articular facet, 
whereby it joins the base of the fourth metatarsal bone. The base 
is flattened below, rough, and somewhat convex above. 

The anterior extremity is more rounded than that of the other 
metatarsal bones, but in other respects similar. The body is pris- 
matic; being flat below, flat internally, and slightly rounded exter- 
nally. 

Of the Toes. 

The toes are five in number, and named numerically, by beginning 
at the great one. They each are formed by three bones called the 
phalanges, with the exception of the great toe, which has but two 
of them. The phalanges are distinguished into first, second, and 
third. In these several respects the toes correspond with the 
fingers. 

Of the first, or Great Toe. 

The first phalanx of the great toe is longer and much larger than 
any other. Its base is large, and forms a deep concavity for re- 
ceiving the end of the metatarsal bone. Its anterior extremity is 



262 SKELETON. 

formed into two small condyles, for being received into the second 
phalanx. This bone is broad and strong, being semi-cylindrical 
above, and flat below. 

The second phalanx corresponds in its appearance with the third 
of the other toes, but is much larger than any of them. Its base 
is broad and flat, and has two superficial cavities for the condyles 
of the first phalanx. The anterior extremity is expanded semi- 
circularly, and converted into a very scabrous surface, for the firmer 
attachment of the soft parts about it. The body of this phalanx is 
constricted in the middle, rounded above, and flat below. 

Connected with the great toe, are two small hemispherical bones, 
lying upon the trochlea of its metatarsal bone, and imbedded in 
the tendons of the small muscles which move the first phalanx. 
They are the sesamoids, and present, superiorly, an articular sur- 
face, covered with cartilage, which enters into the composition of 
the joint; and below, a rounded surface, which has nothing re- 
markable. 

The sesamoid bones, though generally appropriated solely to this 
joint, are yet frequently found elsewhere. For example, in the 
second joint of the same toe — in the first joint of the other toes — in 
the articulation of the first phalanx of the thumb, with its metacarpal 
bone — in the first joint of the fingers — in the knee joint, behind each 
condyle — and, in advanced life, in tendons where they slide upon 
bones. Ancient luxations give a disposition to their development 
in the capsular ligaments of the ginglymous joints, of which a very 
interesting specimen may be seen in the Anatomical Museum, oc- 
casioned by an external lateral dislocation of the elbow. 



Of the Smaller Toes. 

Their phalanges bear a general resemblance to those of the fingers, 
but are neither so large nor so long. 

The first phalanges are successively diminished to that of the 
little toe, and are almost precisely like each other. Their poste- 
rior extremities, or bases, form a cavity deeper in proportion than 
in the fingers, for receiving the ends of the metatarsal bones. The 
anterior extremities are fashioned into two small condyles for form- 



DEVELOPMENT OF THE INFERIOR EXTREMITIES. 263 

ing a hinge-like joint with the second phalanges. The bodies are 
smaller than the extremities, more rounded and narrower than in 
the fingers. 

The second phalanges are very short, the extremities being so 
near each other that the body is of inconsiderable length, particularly 
as regards the last two, where it forms a mere line of separation. 
The posterior end has two superficial cavities for receiving the first 
phalanx; the anterior end is imperfectly fashioned into two little 
condyles for joining the third phalanx. 

The third phalanges have a well-formed articular surface for 
joining the second. The anterior extremity is rough, for the attach- 
ment of the adjoining soft structure. This phalanx of the fourth 
and fifth toe is frequently very imperfectly developed, being a mere 
tubercle with an articular face at one end. 

The structure of the metatarsal and phalangial bones resembles 
that of the other long bones. Porous and cellular at the extremities, 
their bodies are composed of compact lamellated matter, enclosing 
a cancellated texture. 



SECT. IV. — OF THE DEVELOPMENT OF THE INFERIOR 
EXTREMITIES. 

The comparatively small quantity of blood which is sent to the 
lower extremities of the foetus, is the cause of their not being so 
large in proportion to the upper, at the time of birth, as they are 
subsequently. Our wants immediately after birth, and during the 
first months of life, are naturally such as to require but little service 
from the lower extremities, in which is seen a striking correspondence 
between the internal arrangements of the animal economy and its 
actual necessities ; or, in other words, a continued and rigid adap- 
tation of means to produce a certain effect. 

The os femoris at birth presents several peculiarities. Its supe- 
rior extremity being in a cartilaginous state, is placed more at a 
right angle to the body of the bone than it is in the adult. The neck 
is short, which by diminishing the base of support to the trunk makes 



264 



SKELETON. 



the progression of infants more tottering and infirm. The lower ex- 
tremity is also cartilaginous and large. The body of the bone has but 
a very slight degree of curvature, which likewise increases the diffi- 
culty of standing and walking in very young subjects. The patella 
is cartilaginous. 

In the leg the bodies of the tibia and fibula are ossified, but their 
extremities are cartilaginous. The bones of the tarsus, with the ex- 
ception of parts of the os calcis and of the astragalus are cartilaginous. 
The metatarsus and the phalanges are ossified in their middle, but 
cartilaginous at their extremities : their development is not so com- 
plete as that of the corresponding bones of the hand. 

About the fifteenth year, the bones of the lower extremities have 
very nearly the same forms as in the adult : they are all fully ossified, 
with the exception of their extremities not being fused or joined to 
their bodies ; but still in the state of epiphysis, and, therefore, sepa- 
rable either by boiling or long continued maceration. Exclusively 
of this condition, which sometimes remains to the twentieth or twenty- 
fifth year, the epiphyses are as fully ossified as at any subsequent 
period of life. 



SECT. V. ON THE MECHANISM OF THE INFERIOR EXTRE- 
MITIES IN REGARD TO STANDING. 

The os femoris is well adapted by its shape and position to the 
erect attitude. The curvature which its body makes in front has 
the effect of advancing the lower part of it, and thereby keeping it 
in a line with the centre of the trunk ; but if it had been perfectly 
straight, the erect position would have been maintained with great 
difficulty, owing to the centre of the trunk being in advance of this 
bone. Under the latter circumstances, an incessant tendency to fall 
forwards would have manifested itself, which could have been ob- 
viated only by flexing the ossa femorum very much at the hip joint, 
or by keeping one foot always in front of the other. Even under 
the actual arrangement of the skeleton, when muscular support is 
withdrawn from it suddenly, it falls forwards, owing to the weight of 
the parts anterior to the spine being greater than that of the parts 
posterior to it. When muscular action is weakened or badly regu- 
lated, the same tendency to fall forwards is manifested ; children 
continually tumble in that direction : a person in a state of intoxica- 



MECHANISM OF THE INFERIOR EXTREMITIES. 265 

tion, somewhat short of the entire loss of locomotion, not being able 
to sustain the trunk of the body erect by the muscles of the back, 
inclines forwards, and would be precipitated to the ground, were it 
not that at this crisis one leg is automatically advanced, so that the 
base of support is much augmented. But if the individual attempt 
to walk, the continued necessity of keeping a large basis of support 
to prevent the body from falling forwards, urges him into a slow 
running or trotting gait. 

The arrangement of the whole upper extremity of the os femoris 
is also highly favourable to the erect attitude and to locomotion. 
The neck of the bone, by its length and oblique position in regard 
to its body, enlarges transversely the base of its support, and gives 
great stability in preventing the trunk from falling either to the right 
or left ; while it contributes at the same time to the facility of pro- 
gression, in permitting the os femoris to bend forwards and back- 
wards. The lateral or transverse extent of the base, thus obtained, 
cannot be supplied with equal effect in any other way, as a certain 
proportion between the diameters of the pelvis and the length of the 
neck of the thigh bone is indispensable. In females, where the 
transverse diameter of the pelvis is greater than in males, though 
standing is equally secure as in the latter, yet their progression is 
always marked by a want of firmness strongly characteristic of the 
sex. The strength of the articular connexion of the os femoris with the 
innominatum is confirmed by the acetabulum being placed where the 
latter is re-enforced by the linea ilio pectinea, and by the anterior infe- 
rior spinous process; and as the principal weight of the trunk is sus- 
tained by the acetabulum, immediately below the latter process, we 
accordingly find it at this point of the greatest depth. It is also to 
be stated, that the capsular ligament at this part is stronger than else- 
where, thereby conforming strictly to the general purposes of the ar- 
ticular connexion. The capsular ligament is assisted by the liga- 
mentum teres, which, by arising from the lower margin of the 
acetabulum and passing upwards to the head of the os femoris, 
prevents the head from sliding upwards, while it permits it to swing 
freely backwards and forwards in its socket. 

In erection, the bones of the leg are in a line with the vertical 
diameter of the trunk : in this respect they differ very materially from 
the os femoris, which not only inclines forwards in its descent, but 

Vol. I.— 23 



266 



SKELETON. 



also leans towards its fellow internally, and almost touches it at the 
knee. This relative position of the leg and thigh is obtained by the 
greater length of the internal condyle of the os femoris, and also by 
the other peculiarities of form in the latter ; whereas the tibia is nearly 
straight in the direction of its long diameter, and has a horizontal 
articular surface above, whereby it and the os femoris make an en- 
tering angle externally and a salient one internally. Under common 
circumstances, the weight of the trunk is transmitted to the foot ex- 
clusively through the tibia, owing to the fibula not entering into the 
composition of the knee joint, and not being sustained by any bony 
basement at its inferior part. The fibula is principally intended for 
the origin of muscles, and for the lateral security of the ankle joint; 
and may be broken without the accident suspending either erection 
or locomotion. 

The position and shape of the foot concur largely in the general 
object of maintaining the human being in the erect attitude. Fixed 
at a right angle to the leg, and articulated by a surface in the centre 
of its most solid structure, the tarsus, it receives the weight of the 
body perpendicularly upon the astragalus. The latter being the key- 
stone to the arch, diffuses the pressure through the remainder of the 
structure, so that the whole foot is planted against the ground, an 
attitude more fully executed by man than by any other animal. The 
tendency of the body to fall forwards, requires a very considerable 
elongation of the foot in front of the tarsus, in order to increase the 
extent of the base of support in that direction. We accordingly 
find the metatarsal bones not only forming bases for the flexion of 
the phalanges ; but also by their great length, by the flatness of the 
articular faces which they present to the tarsus, and by their conse- 
quent immobility at these points, extending and securing the base of 
the body in that direction to which its gravitation most inclines it. 
The first metatarsal bone, though corresponding in place with the 
first metacarpal, is very unlike it in other respects. Of predomi- 
nating magnitude, but parallel with the other bones and immoveable 
at its base, it is obviously intended for sustaining the body, and 
least of all for prehension and for antagonizing the other bones, as is 
the case with the thumb. 

The points on which the foot is particularly pressed when we 
stand, are the tuberosities of the os calcis, the tuber of the base of 



MECHANISM OF THE INFERIOR EXTREMITIES. 267 

the last metatarsal bone, -with the under surface of the cuboides, and 
the anterior extremity of the first metatarsal bone. The arch of the 
foot, upon which this depends, may be considered in two ways : one 
is in the longitudinal direction, and has its abutments in the os calcis 
behind, and in the ends of the metatarsal bones in front, the other is 
transverse, is but slightly elevated externally, indeed almost flat, 
while it is raised to a considerable height internally. This double 
arrangement is eminently serviceable in many respects : it permits a 
concavity in which the muscles of the toes may repose and act with- 
out being pressed upon by the super-incumbent weight of the body 
— it also permits a free flow of blood and of nervous energy to this 
structure, gives a very elastic base to the whole body, and allows 
itself to be applied to such inequalities of surface as it meets with. 

It has been agitated, by some ingenious inquirers into the original 
condition of man, whether the erect attitude is natural to him and 
not the result of an advancement in civilization. Independently of 
the proofs derived from the authentic reports of travellers concern- 
ing the varieties of the human family, from none of whom have we 
reason to believe that the latter have anywhere been found adopting 
habitually the attitude of quadrupeds; there are evidences derived 
from the general mechanism of the skeleton, still more conclusive, 
that standing is fully natural to us. For example, 1st, The position 
of the foramen magnum occipitis, evidently farther forwards in man 
than in animals, indicates that his voluminous head is to be kept in 
equilibrium by a vertical line of support near the centre of its base. 
2d. The ligamentum nuchas, weak in man, is strong in quadrupeds. 
3d. The curvatures of the spine are so varied as to diminish the 
tendency to fall forward when we are erect. 4th. The direction of 
the orbits of the eyes, which looking forwards, when we stand, and 
enabling the eye to apply itself to a vast circumference, would, in 
the quadruped position, be directed towards the ground, and thereby 
have the sphere of observation reduced to a.few yards. 5th. The 
opening of the nostrils, when we stand, permits odours to ascend 
easily into the nose; in the other attitude this opening would be 
directed backwards. Such are the circumstances, in connexion 
with the head only, which indicate the necessity of the biped posi- 
tion for the full enjoyment of the functions which the Creator has 
given to us. But there are, also, others equally evident in the 
mechanism of the extremities, and of the parts of the trunk to which 
they are attached. Thus, 1st, The breadth of the pelvis, and the 



268 SKELETON. 

actual obliquity of its superior strait, in regard to the spine, prevent 
us from falling to one side, and, at the same time, brings the lower 
extremities immediately in a line with the spine. 2d. The length 
of the neck of the os femoris, and the size of its condyles. 3d. The 
articulation of the knee, which permits the leg to be brought into a 
line with the os femoris, a position impracticable in quadrupeds. 
4th. The foot being articulated at a right angle with the leg, and 
having its tarsus and metatarsus so well developed. 5th. The pre- 
dominance of the transverse diameter of the thorax over the vertical, 
which, with the great length of the clavicle, and the shape of the 
scapula, unfit the latter for assisting much in progression. 6th. The 
shape of the hand, calculated to seize upon objects, but from the 
length of its phalanges not suited to sustain the body. 7th. The 
mode of articulation at the wrist, which, from its mobility and 
weakness in the direction to which the weight of the body would 
be applied to it, could not be brought to support it advantageously. 
And, lastly, the great disproportion of length, in the adult, between 
the upper and lower extremities, when an attempt is made to walk 
like the quadruped. 

In considering the skeleton of the very young child, it is worthy 
of remark how closely its mechanism, with the exception of the 
head, corresponds with the habits of early life. A spine, nearly 
straight, and a pelvis, the lateral diameter of whose cavity is so 
small that the transverse base of support is much diminished, render 
erection inconvenient. Lower extremities shorter in proportion 
than the upper ones, having thigh bones nearly straight; also, the 
articulations of the knee not admitting of a full extension of the leg. 
All these circumstances prove that the quadruped position, incon- 
venient and intolerably irksome when continued for a length of time 
in the adult, is natural to the young infant. 

The space between the ossa femorum, produced by the breadth 
of the pelvis and the length of their necks, and, therefore, always 
considerable above, varies below in different individuals. A certain 
distance at the latter point seems to be indispensable to convenient 
and graceful progression. Thus, when it is in excess, it produces 
the defoimity called bandy legs, and causes a tottering gait, such 
as may be mimicked, at any time, by walking with the legs in a 
state of abduction: but, when diminished, it is called knocked 



MECHANISM OF THE INFERIOR EXTREMITIES. 269 

knees, and interferes with the firmness of the step by causing the 
centre of gravity to pass, alternately, through the internal condyles 
of the ossa femorum, instead of falling exactly between them. 

The firmest position in which we can stand is that in which the 
feet are perfectly straight and parallel with each other, so as to 
form a square base for the support of the trunk. If from this posi-r 
tion the toes be turned either inwards or outwards, the consequent 
reduction of the antero-posterior diameter of the base, causes less 
resistance to ihe natural inclination of the trunk forwards. What- 
ever may be the grace and the ultimate intention of the first position 
in dancing, to wit, that of having the feet nearly in the same line, 
with the heels touching and the toes outwards, it is certainly the 
most unfavourable attitude for ease in keeping the body erect that can 
be adopted ; for the base of support being diminished, both by the 
length of the body of the os calcis, and by that of the foot, anterior 
to the ankle joint ; the trunk is continually inclining either forwards 
or backwards, and is prevented from falling only by the alternate 
action of the muscles behind and in front. 

When we are upon the knees, the base of support for the trunk 
being entirely withdrawn in front, it is necessary, in order to main- 
tain the position and to prevent falling forwards, that the hip joint 
be flexed so as to throw the weight of the body entirely behind the 
thigh bones. The position is one of so much restraint and fatigue 
upon the muscles, that it can be maintained for a long time, only by 
some artificial support in front, or by the buttocks falling down upon 
the legs, and resting against them. 

The position we assume on being seated in a chair, is the easiest 
of any of those in which the trunk is kept erect or nearly so. The 
length of the lever, represented by the whole length of the skeleton, 
is then diminished one half; consequently, any preponderance of it 
at particular points, above, bears with less force upon the base. 
The base itself is much augmented by the amplitude of the buttocks, 
and by the horizontal position of the thigh bones in front ; and may 
be also increased, at pleasure, by the extension of the legs. If, 
under such circumstances, the trunk of the body be slightly advanced, 
its equilibrium is so easily maintained as to require but a very little 
muscular action to continue it. The most exposed part of thebas^ 

23* 



270 SKELETON. 

is backwards ; and, if the trunk be kept perfectly erect, there is some 
tendency of it to fall in that direction. Hence, the utility of backs 
to seats, and the fatigue from such as have not. 



SECT. VI. ON THE MECHANISM OF THE INFERIOR EXTRE- 
MITIES IN REGARD TO LOCOMOTION. 



1. Of the Motions of the Thigh. 

These like the motions of the os humeri, upon the scapula, con- 
sist in extension, flexion, abduction, adduction, rotation, and cir- 
cumduction ; but in consequence of being performed upon an im- 
moveable basis, the acetabulum, they are much less extensive. In 
order that they may be understood well, it will be useful to assume 
certain points of reference in the os innominatum and os femoris. 
These are the trochanter major, the pubes, and the anterior superior 
spinous process of the ilium. In standing, the lower external part 
of the trochanter major, where it forms a bulge on the side of the 
thigh bone, is on a horizontal line with the upper part of the sym- 
physis pubis. A triangle, described by lines drawn from the ante- 
rior superior spinous process to the symphysis pubis — from the lat- 
ter to the point mentioned of the trochanter, and from the latter to 
the anterior superior spinous process, will be nearly a rectangle, of 
which the base is above, and the shortest side behind. 

The flexion of the os femoris is that motion in which its lower ex- 
tremity is carried forwards. It is performed with great ease and 
freedom, in consequence of the arrangement of the articular surfaces 
of the bones and of the capsular ligament. The head revolves freely 
in the acetabulum, the ligamentum teres is put into a slight tension, 
and the end of the trochanter major approaches the sciatic notch. 
The extreme point of this motion is the one preserved by the os 
femoris of the fetus in utero. 

Extension is the reverse of flexion. When the latter has been 
performed, extension restores the thigh bone to its vertical position, 
and carries it some degrees farther, but cannot be executed to the 
same extent behind, that flexion is in front. When pushed to an 
extreme, it brings the trochanter major under the inferior anterior 



MECHANISM OF THE INFERIOR EXTREMITIES. 271 

spinous process of the ilium, and the round ligament is put very 
much upon the stretch ; it is finally, arrested by the lower part of 
the neck of the os femoris lodging against the posterior elevated 
margin of the acetabulum, and by the thickened part of the capsule, 
in front and above, being so much distended as not to yield farther 
without laceration. 

Abduction is the act by which the thigh bones are separated. 
When carried to an extreme, the under part of the head of the os 
femoris leaves the acetabulum, and distends very forcibly the cap- 
sular ligament at this point. The superior fasciculus of the round 
ligament is strongly extended; but the inferior fasciculus is kept 
easy, and, indeed, somewhat relaxed. This motion is arrested by 
the trochanter major striking against the ilium; without which it 
would be much more extensive, as the capsular ligament is strained 
at its weakest point, and relaxed at the strongest. 

Adduction is the reverse of the last. The muscles which produce 
it, the adductors, from their situation and course, are unable to 
give an extent to this motion much beyond the act of reinstating 
the thigh when it has been adducted. In this respect they are much, 
less influential than the great pectoral muscle which adducts the os 
humeri. The articular surfaces of the bones are suited to a much 
greater latitude of this movement, but it is arrested both by a defi- 
cient power in the muscles, and by the strong upper part of the cap-- 
sular ligament being put upon the stretch. 

Circumduction is the regular succession in a circle of the four pre-, 
ceding motions, and is much less extensive in the os- femoris than 
in the os humeri, for the reasons stated. The centre of the circle, 
or cone, thus described, is the head of the bone, and it is much 
more extensive anteriorly and externally than posteriorly and in- 
ternally. 

Rotation, owing to the length of the neck of the os femoris, is ex- 
tremely well marked, and is indicated by the trochanter major 
moving backwards and forwards. The radius of the circle thus de- 
scribed, is the distance between the centre of the head of the os 
femoris and the bulging external part of the trochanter major. The 
rotation outwards or backwards is more fully and easily performed 



272 SKELETON. 

than the reverse, owing to the number and favourable position of 
the muscles causing it, many of which are specially appropriated to 
its production, and some others partially so. This movement is ar- 
rested by the neck of the bone striking against the acetabulum be- 
hind, and by the tension of the capsular ligament in front. Rota- 
tion, forwards, having but few muscles to produce it, and they 
neither specially devoted to it, nor acting very advantageously for 
the purpose, is arrested by the neck of the bone striking against the 
fore part of the acetabulum, by the tension, behind, of the capsular 
ligament, and also, by that of the ligamentum teres. When the con- 
vexity and the neck of the os femoris look directly forwards, it is 
indicated by the great toe pointing in the same direction. 



2. Of the Motions of the Leg. 

The movement of the leg upon the thigh is that of flexion, of ex- 
tension, and a very partial degree of rotation. 

In flexion, the head of the tibia slides backwards upon the con- 
dyles of the os femoris, which are prolonged behind, for the purpose 
of extending this motion. It is checked, when carried to an ex- 
treme, by the posterior margin of the tibia striking against the os 
femoris, and by the tension of the ligament of the patella. In the 
mean time, the lateral, the crucial, and the posterior ligaments are 
relaxed. The patella, always stationary, and at the same relative 
distance in regard to the head of the tibia ; slides downwards upon 
the trochlea of the os femoris, and in the flexed position sinks be- 
tween the condyles, so as to come in contact with the ligamentum 
mucosum. 

In extension, the patella rises upon the condyles, and becomes 
prominent ; the lateral ligaments are rendered somewhat tense, and 
the motion is finally checked, by the resistance of the crucial and of 
the posterior ligaments of the articulation. 

The rotation of the bones of the leg can only be performed when 
they are flexed, and the ligaments, generally, thereby relaxed, in 
which position a very limited motion, inwards and outwards, is per- 
ceptible. The motion outwards, is the more extensive of the two, 



MECHANISM OF THE INFERIOR EXTREMITIES. 273 

in consequence of the arrangement of the crucial ligaments, which 
are separated from each other by it. The motion, inwards, is limit- 
ed by these ligaments being brought immediately by it into close 
and resisting contact with each other. In either case, however, the 
posterior and the lateral ligaments all contribute, ultimately, to arrest 
the motion. 

In all these conditions of the leg, the semi-lunar cartilages slide 
somewhat upon the head of the tibia. 

The articulation between the tibia and the fibula is such as to 
admit of no motion whatever below ; but, above, a limited sliding 
backwards and forwards is performed by the fibula upon the tibia. 
This movement is made more perceptible in cases of extreme ema- 
ciation, and in general relaxation of the muscular system. 



3. Of the Motions of the Foot. 

The general motions of the foot upon the bones of the leg are 
flexion, extension, and an inconsiderable inclination inwards and 
outwards. 

In flexion, the astragalus rolls backwards in the articular cavity 
formed by the tibia and the fibula, and is arrested by the anterior 
upper part of the astragalus coming in contact with the articular 
margin of the tibia. The ligamentous fibres and the synovial mem- 
brane, in front of the articulation, are relaxed ; those behind are in a 
state of tension, as well as the tendo-achillis, and the other tendons 
there. Luxation from an excess of this motion is almost impossible. 

In extension, the foot is brought with the point downwards, so as 
to have its upper surface almost on a line with the bones of the leg. 
The astragalus glides forwards; the tendons, on the back of the 
joint, are very much relaxed. The joint itself is in a state the 
reverse of the preceding. 

In the lateral motions, the sole of the foot is caused to present 
itself either obliquely inwards or outwards, whereby it may be ac- 
commodated to any inclined surface on which we walk. The first 
position is checked by the internal malleolus, and the tension of the 



274 SKELETON. 

external lateral ligaments; the second, by the external malleolus, 
and by the tension of the internal lateral ligament. These motions 
constitute the adduction and the abduction of the foot ; and by a 
regular succession with its flexion and extension, communicate a 
very limited and embarrassed species of circumduction. 

The bones of the tarsus, for the most part, have a very obscure 
motion upon each other, with the exception of the articulation be- 
tween the astragalus and the scaphoides, and between the os calcis 
and cuboides. At these points the movement upwards and down- 
wards, makes a sort of flexion and extension of the fore part of the 
foot, which is very distinct. A species of twisting, or oblique gliding, 
is also slightly perceptible there. 

The bones of the metatarsus are susceptible of a slight elevation 
and depression, which, almost imperceptible at their bases, become 
sufficiently obvious at their anterior extremities. They also may be 
slightly approximated, at their fore parts, by the action of muscles, 
and by external compression. When the weight of the body is 
thrown upon them, they separate from each other, and the metatar- 
sus loses, in some degree, the arched form of its anterior extremity 
below. 

The phalanges of the toes have the same motions with those of 
the fingers, except that they are more restricted. The first ones, 
therefore, perform flexion, extension, adduction, abduction, and cir- 
cumduction; the last two have only flexion and extension. The 
extension of the first phalanges is more extensive than their flexion, 
from whence results an important advantage in walking or in stand- 
ing upon the toes. The shortness of the second and third phalanges 
of the small toes, together with the thickness of the sole of the foot 
contiguous to them in their extreme flexion, causes them rather to be 
doubled up on themselves, than on the sole of the foot. 



On the General Motions of the Lower Extremities. 

These may be resolved into three; walking, running, and 
leaping. 



MECHANISM OF THE INFERIOR EXTREMITIES. 275 

In walking, though the first step may be taken in a variety of 
relative positions of the lower extremities to each other, yet it will 
make the investigation more clear to suppose the individual standing 
erect, with the two feet precisely on the same plane, and giving equal 
support to the trunk. The first step is then taken, by detaching the 
foot of one side from the ground; in order to do which, the thigh is 
bent upon the trunk, the leg upon the thigh, and the limb by being 
thus elevated becomes shorter. At this period the ankle joint re- 
mains at rest, with a slight inclination of the toes downwards. By 
the subsequent relaxation of the muscles of the limb advanced, with 
an inclination of the trunk to the same side, the limb is caused to 
descend upon the ground. These are the only motions when the 
step is short and easy ; but, when a long stride is taken, by which 
the limb is put very much in advance of its fellow, in order to bring 
it to the ground, the pelvis is caused to rotate forwards on the head 
of the stationary thigh bone, whereby the trunk of the body, instead 
of presenting the sternum forwards, has it turned to one side. 

When a step has been taken so as to leave one inferior extremity 
advanced before the other, for example the left, the limb behind is 
brought forward by the following mechanism; — The left foot re- 
maining fixed, becomes the point of support to the trunk ; and the 
right, which is behind, is elevated successively, from the heel to the 
toes, by the action of the muscles on the back of the leg, and rests 
upon the phalanges. The effect of this position is to elongate the 
right inferior extremity to the amount of the distance between the 
fore part of the ankle joint and the anterior extremity of the meta- 
tarsus, whereby that side of the pelvis is pushed forwards, and a 
rotation in advance impressed upon it. By the latter impulse, the 
foot of that side is wholly detached from the ground, the thigh being 
flexed at the same moment at the hip-joint, and the leg flexed at the 
knee, the whole extremity is carried forward and fixed upon the 
ground, after the manner described in the first step. Ordinary pro- 
gression results, then, from the regular succession of the last motion 
in the two extremities. In regard to the impulsion of the pelvis 
from the foot behind, this will probably take place in every case, 
more or less ; it may, however, be reduced very much by a certain 
extent of flexion at the knee joint ; and the want of it not be felt, be- 
cause other powers concur to produce the same impulsion ; as cer- 
tain muscles, and also the momentum of swinging the lower extre- 
mity forward. 



276 SKELETON. 

An equality of length in the lower extremities is indispensable to 
graceful and regular progression. If one of them be shortened from 
any cause whatever, it is manifested in the gait, by an unusual sink- 
ing of the pelvis on the defective side, at the moment the foot is 
brought to the ground, and from the continuity of the pelvis with the 
upper parts of the body, a considerable lateral inclination is commu- 
nicated to the latter in the same instant. The pains frequently taken 
to conceal this defect, disguise it very imperfectly, unless the short- 
ness be only such as may be supplied by a shoe with a sole thicker 
than that of the other foot. Where the shortness arises from luxa- 
tion upwards of the os femoris, a crutch is the best substitute for 
sustaining that side of the pelvis. 

In running, the position of the feet is somewhat different from 
what it is in walking ; they are extended so as to support the trunk 
on the phalanges alone, instead of on their soles: whereby a double 
advantage is obtained, that of keeping the lower extremities at their 
greatest possible length, and also of enabling them to detach them- 
selves quickly from the ground. The velocity here is the principal 
difference between it and walking, yet there are some peculiarities. 

The trunk of the body is kept continually and largely inclined 
forwards, which enjoins the necessity of a quick successive advance 
of the lower extremities to prevent it from falling. This position, 
also, by advancing the bony points, from which arise several of the 
muscles used in the extension of the thigh, removes these muscles 
more from the line of their contraction, and thereby enables them to 
act more advantageously and promptly. As each pace on these oc- 
casions is taken to the fullest stretch, the pelvis is rotated forwards 
from side to side, alternately upon the head of the os femoris, which 
may be fixed at the time. The face being directed forwards, whatever 
rotation in the vertebrae can occur, is then performed. As the pelvis 
communicates its motions to the trunk, so the latter carries its own 
to the upper extremities ; which are thereby slung, alternately, 
backwards and forwards, and are brought, continually, to adjust the 
centre of gravity, which is then more in danger of being lost than in 
ordinary walking. 

The ascent of an inclined plane, either by walking or running, is 
attended with unusual fatigue and difficulty, for the following rea- 
sons : In order to advance the thigh, it is necessary to give it great 
flexion at the hip-joint, the knee must also be bent in an equal de- 



MECHANISM OF THE INFERIOR EXTREMITIES. 277 

gree, and the foot be flexed, in order to adjust it to the surface 
against which it reposes. To bring forward the other extremity, it 
requires an equal flexion at the hip and knee ; besides which, its 
heel being below the phalanges, the foot must perform a full rota- 
tion at the ankle joint. The difficulty is somewhat diminished by 
stepping only on the phalanges. As, in these cases, the trunk of 
the body, to preserve its equilibrium, must be inclined forwards, 
there are certain acclivities, which, though they furnish a base suffi- 
ciently large for the foot, are yet impracticable from not allowing the 
trunk to be thrown forwards. 

The descent of an inclined plane is more easy, because it re- 
quires but little flexion, in the articulations mentioned, to bring the 
extremity behind on a line with that in front ; and its subsequent 
descent is produced by keeping it almost straight, and shortening 
the extremity which is fixed. Running is then attended with some 
inconveniences, for the impulsion, forwards, which this motion com- 
municates to the trunk, assisted by the inclination of the plane in 
that direction, determines a fall, inevitably, without a successively 
accelerated advance of the hind leg. We see frequently, in the de- 
scent of a very inclined hill, a step, at first guarded and leisurely 
taken, converted, unavoidably, into a full run, to prevent the body 
from being precipitated forwards to the ground. 

In jumping, the whole body is projected abruptly from the ground, 
either in a vertical or oblique direction. 

In the first, the lower extremities are shortened by a general flexure 
of their articulations, and, by a very sudden and simultaneous exten- 
sion of them, the resistance of the ground causes the whole frame to 
mount upwards, till its gravitation causes the momentum to cease ; 
it then descends on the same principle with projectiles, generally. 
In the oblique leap, there is the same flexion in all the articulations 
of the lower extremities, with the addition of an inclination, forwards 
of the trunk. At the moment when the limbs straighten themselves, 
the trunk is projected, not only upwards, but forwards, owing to its 
inclination, and describes in its ascent and descent a parabola. In 
this effort, the space traversed will be more considerable, if a pre- 
vious horizontal momentum has been communicated to the trunk by 
running several steps before the leap be made. 

The more oblique the leap is, the greater will be its extent, to 
effect which the trunk must be inclined proportionably forwards. 

Vol. I.— 24 



278 SKELETON. 

But to obtain this inclination without falling, it is necessary for one 
of the lower extremities to be very much advanced at the moment 
of springing with the other, so as to convert the motion into a very 
long step. With this position of the lower extremities, a much 
longer space can be cleared than if they were kept together.* 

* For a further exposition of the principles of locomotion, see Joh. Alph* 
Borelli de Motu Animalium, 1710. Haller, Element. Physiol, torn. iv. 1757. 
Bichat, Anat. Descript. 1801. Barthez, Nouvelle Mechanique des Move- 
mens de 1'Homme et des Animaux, 1798. Encyclop. Anat. t. ii. Paris, 1843. 



BOOKI. 

PART III. 

ARTICULATIONS. ; 

CHAPTER I. 

HISTOLOGY OF THE CARTILAGINOUS SYSTEM.* 

Cartilages (Cartilagines, Systeme Cartilagineux,) besides being 
the nidus for bone in forming the skeleton, supply permanently the 
place of bone in many parts of the human body, as in the space be- 
tween the ribs and sternum, in the larynx, in the external ear, in the 
nose, and elsewhere. They are also to be found in all the move- 
able, and in several of the immoveable articulations. Wherever 
placed they may be recognised by their whiteness, by their flexibi- 
lity, by their great elasticity, and by a hardness only short of that of 
the bones. There are many animals whose skeletons are entirely 
cartilaginous, as the chondropterous or cartilaginous fishes, so ex- 
cellent a substitute is cartilage for bone. 

From the preceding distribution of the cartilaginous tissue, it is 
divided into articular cartilages, or those which cover the ends of 
bones in forming the joints ; and into the cartilages of substitution, 
or those that supply the place of bone, so as to form a flexible skeleton 
or basis for the superimposed structure. The instances of the latter 
are, for the most part, fibro-cartilages or cartilage and ligament in 
union. 

* Anat. Atlas, Figs. 93, 94, 95, 96. 



280 SKELETON. 

Cartilages have neither medullary canals nor areola? in them like 
those of bones. The immersion of them in boiling water dissolves 
into a jelly, such as are found upon the articular surfaces of the 
bones, and a few others ; but, such as supply the place of bone, 
though softened by the process, are not rendered by any means so 
gelatinous. Their chemical analysis, according to Mr. I. Davy, is 
gelatine, 44.5 ; water 55.; phosphate of lime, 0.5. The testimony 
of different experimenters, upon the latter point, does not coincide, 
and their results must vary according to the kind of cartilage, and 
the period of life. 

Cartilages are composed of a tissue exclusively their own, and 
of parts which they have in common with other organs. The first 
has some very distinguishing properties. It resists putrefaction, 
either with or without maceration, longer than any other tissue, 
except the bones. In the midst of gangrene it preserves its appear- 
ance almost unchanged. Boiling gives it a yellow colour, causes it 
to swell, and, if protracted, the gelatinous portion is dissolved. 
When dried it becomes of a semi-transparent yellow, diminishes 
in bulk, and loses its elasticity ; in these respects resembling liga- 
ments and tendons. From their bibulous structure they very readily 
swell out again upon immersion in water. 

Cellular substance exists, in very small quantities, in cartilage, 
and is, therefore, not readily demonstrated ; it is, however, made 
manifest by maceration, and by the action of boiling water : the 
latter, by dissolving the gelatinous portion, leaves a membranous 
and cellular structure. It is also stated that in certain diseases, the 
gelatinous portion being less abundantly secreted, the cellular is left 
in a soft spongy condition. 

In a healthy state, no blood vessels can be seen in articular cartilages ; 
yet there are the strongest proofs of a species of circulation going on in 
them, either by very fine capillary vessels, or an interstitial absorption. 
All experienced anatomists have seen, in subjects affected with jaun- 
dice, the entire cartilaginous system losing its brilliant whiteness, and 
becoming of a light yellow. The cartilages, or rather fibro-carti- 
lages, which supply the place of bone, and act in that way, as parts of 
the skeleton, exhibit a decided presence of blood vessels in small 
quantity and not difficult to be detected in an advanced period of life by 
minute injection, or by a spontaneous congestion of blood in them; 
but in extreme old age, when ossification invades, to a variable ex- 
tent, all of these structures, they, like the primary ossific cartilage, 



THE CARTILAGINOUS SYSTEM. 281 

have a free evolution of blood vessels, easily seen by the naked 
eye. This is especially the case in the cartilages of the ribs, whose 
ossification is very common, but seldom so perfect as in the regular 
bones, there being a very large proportion of gelatine for the amount 
of calcarious matter, and generally found most abundant near the 
centre. 

Neither absorbents nor nerves have been traced into cartilages, and 
it is not possible to prove conclusively, their existence by the cir- 
cumstances of disease. We only know, that in inflammations of the 
joints, terminating by anchylosis, the cartilages are absorbed ; and 
that in some cases, even without evident inflammation, the cartilage 
is removed from a joint as if it had been worn away. Ulcerations 
of the arytenoid cartilages are spoken of as common, by the French 
anatomists ; and I have, since the first edition of this work, seen 
several instances in chronic Laryngitis ; but it has not occurred to 
me to see any others unequivocally in this state : the late Dr. Phy- 
sick's experience is also the same with my own. It must, however, 
be borne in mind, that these approximate like the costal cartilages to 
the fibrocartilaginous system. Possessed of no animal sensibility 
in the natural state, it is doubtful whether cartilages ever have it, or 
can inflame, as the pains in inflammations of the joints may arise 
from the synovial membranes. 

In the embryo, the osseous and cartilaginous systems are con- 
founded, so as to present a homogeneous, mucous or pulpy appear- 
ance ; they only become distinct by the deposite of calcarious mat- 
ter in the bones : when the latter are somewhat advanced, the car- 
tilages, which are to remain such, have also additional consistence, 
and more of a proper cartilaginous look ; but the appearance is gene- 
rally unsatisfactory, by which one can learn to distinguish the car- 
tilages that are to remain such, from the cartilaginous rudiments of 
the bones. The following circumstance, however, is pointed out 
by Bichat : in the cartilages of ossification, there is a vascular net- 
work between the cartilage and the ossification which has occurred, 
and owing to the interposition of it, the two may be easily separated. 
But in the permanent cartilage, this net-work does not exist between 
the proximate surfaces of the bone now formed and of the cartilage, 
consequently they adhere with a tenacity not admitting of a rigid 
separation from one another. 

The organic structure of every cartilage consists in a transparent 
amorphous substance, or matrix, with cells or vesicles numerous^ 

24* 



282 



SKELETON. 



interspersed through it. These vesicles are ovoidal or of a notched 
lenticular shape, somewhat resembling a broad bean. In the mature 
cartilage the parietes of such cells cannot be well distinguished from the 
amorphous substance, which in this state is called the hyaline or vitre- 
ous cartilage. The cells themselves, now called Cartilage corpuscles, 
are filled with a softer substance, in which their nuclei repose appa- 
rently for the most part unattached to the walls of the cells, but not 
universally so. The nuclei have within them nucleoli. 

In the mature state, cartilages present much diversity in their inti- 
mate texture, but while in a state of evolution they are much alike. 
Thus, the structure originates in cells as the rest of the body; but 
between the cells or vesicles is a larger proportion of hyaline or 
amorphous matter. The latter increases with the growth of the cells, 
and new cells spring out from cytoblasts or germinal particles exist- 
ing in it. The early cells are much disposed to throw off shoots 
from their nuclei, and thus groups of cells are formed. 

Permanent cell cartilages of the above description are seen in that 
of the septum narium, alse and point of nose, eyelids, external ear, 
Eustachian tube, larynx excepting epiglottis, trachea and its branches, 
the articular cartilages, costal, and ensiform of the sternum. 

In transient cell cartilage, that which is, for example, to be the 
nidus for bone, the vesicles or cells are very numerous in comparison 
with the matrix, and vary in size as well as in shape, some being 
round, others oval, and others compressed ovoidal. They, as stated 
in regard to the proeess of osteogeny, being first of all irregular in 
position, yet disposed into a sort of columnar or shafted arrange- 
ment, the ends of which point to the surface of ossification. 

The cells of cartilages vary considerably, according to the carti- 
lages themselves, in regard to both size, shape, and number. In 
the cartilages of the ribs they are from ^ to jfe of an inch in dia-. 
meter, while in the articular cartilages they are from T i?W to *fo of 
an inch. 

If the base of cartilage be pure and transparent, the cartilage is 
white or of a bluish white ; if, on the other hand, the fibrous element, 
prevail, then the cartilages have a yellowish tint. The cartilages 
which have a homogeneous base are called True — and those with a 
fibrous base are called False. There are, however, several of these 
bodies so much on the transition line that the distinction is observed 
with some difficulty, and there are changes depending upon the pro- 



THE CARTILAGINOUS SYSTEM. 283 

gress of life from early infancy to old age, which also interfere with 
this classification. 

Microscopic observers have remarked* that the closest resem- 
blance exists between the structure of cartilages and of vegetables, so 
that an exact identity prevails in regard to the form-^the grouping 
and even the mode of origin of their vesicles or cells. In all the 
mammalia, the state of ossific cartilage is uniform — this condition 
being varied only according to their degree of maturity for the re- 
ception of bony deposites. The permanent cartilages vary less in 
their appearance at different epochs, and their cells discovered by 
Purkinje are more closely packed as the cartilage is of more recent 
formation. 

The peculiar character of cell cartilage is derived from the presence 
of a substance called Chondrin, which resembles, much, ordinary- 
gelatin, but requires a longer process of boiling for its solution in 
water. Like gelatin it solidifies on cooling, and when the moisture 
is completely driven from it, it looks like hard glue. It differs from 
gelatin in not being precipitated by Tannic Acid, a difference is also 
observed in the case of several other re-agents. Thus, for example, 
it forms precipitates with acetic acid, alum, acetate of lead, and 
protosulphate of iron, which do not disturb gelatin, and it contains 
upon chemical analysis less nitrogen and more hydrogen. 

The nutrition of cartilage it is believed is accomplished through 
the agency of the cells. The cells contiguous to the blood vessels 
of the region, eliminate from the latter the requisite materials, and 
transmit them to the proximate series of cells, the latter do the same 
in their order, and so on in succession until the whole is nourished. 
In cases where from inflammation there has been a vascularity in 
articular and other cell cartilages, these vessels are formed in a new 
tissue, the product of the inflammatory process. 

It has been ascertained that all the cartilages of a foetus, both the 
ossific and the permanent, are composed of chondrin, but so soon 
as ossification commences, the chondrin of the former is changed 
into gelatin, while it remains constant in the permanent cartilages, 
unless they also change ; this has led to the conjecture that as 
ehondrin is nearer alike to proteine, so it is merely an intermediate 
Stage for the formation of gelatin. 

As the individual reaches adult age, the cartilages acquire the 
* Gerber, Gen.. Anat. p. 171. 



284 



SKELETON. 



strength, whiteness, and great elasticity which distinguish them. 
In old age they become yellowish, more brittle, and are, as said, 
generally disposed to ossify. Those of [the ribs and larynx are fre- 
quently ossified at forty years of age. The ossification of those of 
the moveable joints is rare, and begins at a more advanced period. 
In the first two it begins commonly near their centre, and in the last 
on the surface. 



ACCIDENTAL DEVELOPMENT OF CARTILAGES. 

The unnatural development of cartilages, in the tissues and organs 
of the body, to which they are very slightly allied in their nature, 
is a circumstance, by no means uncommon, and is met with an- 
nually, in most of its varieties, in our dissecting-rooms. As there 
is a great disposition in such cartilages to ossify, they are presented 
in the several gradations from a soft gelatinous body to that of per- 
fect bone. They occur in the articulations; in the lungs, and form 
there fistulous passages ; very frequently on the surface of the spleen; 
in the pleura; in the fibrous coat of the large arteries, particularly 
the arch of the aorta; and in the semi-lunar valves of the same; in 
the ovarium, when it becomes dropsical; and also in many other 
parts of the body. 

The cartilages which are found loose in the joints and floating 
about there, begin, for the most part, in the fibrous structure* ex- 
terior to the synovial membrane; the latter is protruded inwards by 
them, and gives them a covering resembling the finger of a glove. 
As these bodies are small and rounded, when they protrude into 
the joint the synovial membrane forms a pedicle or base to them, 
which is finally ruptured, and then the cartilage becomes loose. 
These bodies are generally ossified in their centre, of course they 
have gone through the usual progress and phenomena of ossification. 
The other forms of preternatural cartilage are much disposed to 
ossify in the arteries, but not so much so in the other organs. In 
these cases they are laminated and adhere by their surfaces, very 
closely, to the contiguous structure, so as to be membranous. M. 
Laennec has seen a cartilaginous transformation of the mucous 
membrane of the urethra; M. Beclard of the mucous membrane in 

* Beclard, Anat. Gen. 



DEVELOPMENT OF CARTILAGES. 285 

the vagina, attended with prolapsus uteri, and also of the prepuce 
of an old man who had a phymosis from birth. 



OF THE PERICHONDRIUM. 

All the cartilages, except the articular ones, are invested by a 
membrane called perichondrium, (perichondre.) It is best seen on 
the larynx, and on the cartilages of the ribs. Its structure is 
fibrous, and corresponds so fully with that of the periosteum that 
it may be considered the same sort of membrane. It is, however, 
less vascular than the periosteum, and adheres to the cartilages 
with less force, owing to the fibrous connexion between them being 
not so abundant. Bichat's experiments prove that the cartilage is 
much less affected by the loss of this membrane, than the bone is 
by that of the periosteum : its uses are no doubt the same. 



OF THE ARTICULAR CARTILAGES. 

To this class we refer, exclusively, such as adhere by one surface 
to the articular facings of the bones, and present the other surface 
to the cavity of the joint. Every moveable, and some of the im- 
moveable articulations, have their surface uniformly thus incrusted, 
to a thickness varying from the fraction of a line in the smallest 
joints, to one line in the largest. The cartilage itself is rather 
thinner near the margin of the articular surface, when the latter is 
convex, than it is near the centre; on the contrary, when the surface 
is concave, the cartilage is thickest near its periphery. 

These cartilages, when subjected to a maceration of six months, 
are stripped of the reflection of synovial membrane, which covers 
their articular surfaces, and are resolved into fibres, one end of 
which adheres to the bone and the other end points to the joint. 
If the preparation be then dried, the distinction of fibres becomes 
more manifest. 

The most successful injections, closely examined with a micro- 
scope, demonstrate the defect of blood vessels in them. The ves- 
sels are uniformly seen to terminate at the circumference of the 
cartilage and at the face which adheres to the bone, but never to 
penetrate it. Their organization is, therefore, extremely simple, 



286 



SKELETON. 



and such as subjects them to but few morbid alterations. When 
partially removed from the bone the latter occasionally reproduces 
them, but the edges of the new and of the old production do not 
unite. I have, in cases of inflammation of the joints, seen the 
fibres of these cartilages much longer than usual and detached from 
each other. When a joint is laid open by a wound, and suppu- 
rates, the cartilage softens and disappears from the circumference 
to the centre.* 



CHAPTER II. 

Histology of the Fibro or Ligamento-Cartilaginous 

System.* 

This set of organs (Systeme fibro- cartilagineux) has been placed by 
anatomists, indiscriminately in the cartilaginous or in the ligament- 
ous system, in consequence of its participating in the characters of 
both ; it, however, from its importance, should have a distinct posi- 
tion. There are three varieties of this system. The first presents 
itself in a membranous state, and is represented by the external ear, 
by the alse of the nose, by the cartilages of the eye-lids, and by the 
trachea. The second is represented by the inter-articular cartilages 
of the moveable articulations, as of the knee, the wrist, lower jaw, 
and also by the inter-vertebral matter which holds the bodies of the 
vertebrae together. And the third is represented by the trochleae and 
sheaths, formed on the surface of bones for the gliding of tendons. 

The principal constituent of this system is a strong fibrous matter, 
which is intermixed with the cartilage, and has in some places its 
surface covered by the latter. The fibres even by superficial obser- 
vation may be traced in various directions : in some places they are 
parallel ; in others intermixed and crossed very much ; in others con- 
centric. Their strength is of the first degree. The cartilaginous 

* Bichat, Anat. Gen. The same author speaks of the idiopathic ulceration 
of cartilage, as a result of its inflammation. The late Dr. Physick, whose ex- 
perience was equal, denied both. 

f Anat. Atlas, Fig. 97. 



FIBRO OR LIGAMENTO-CARTILAGINOUS SYSTEM. 287 

part fills up the intervals between the fibres, and gives to the whole 
structure its whiteness and elasticity. 

The Fibro-cartilages may be converted by the action of hot water 
into gelatine, but the process is slower than in the simple cartilage. 
The membranous, or first variety, differs, however, from the other 
two in this respect ; for if it can be reduced at all into gelatine, the 
quantity it yields is not perceptible. The fibro-cartilages contain 
few or no cartilage corpuscles or cells, and, according to Midler, do 
not yield chondrin upon being boiled. 

This system is destitute of perichondrium, with the exception of 
the first variety, in which it is distinguishable ; but the others either 
adhere to the bone, or are covered by a synovial reflection ; their 
margins adhering in such cases to the contiguous ligamentous 
structure. 

There is a very small quantity of cellular tissue in this system. 
Artificial injection manifests but few blood vessels in it; if the ani- 
mal, however, be strangled for the purpose, the blood by accumu- 
lating in the capillaries becomes sufficiently apparent. 



CHAPTER III. 
Histology of the Ligamentous or Desmoid Tissue* 

SECT. I. 

The Desmoid Tissue, (Textus Desmosus, Systeme Fibreux,) is 
very generally diffused in the human body, has a very close con- 
nexion with the cellular texture, and is continuous with it in divers 
places. It may be known by its whiteness, the firmness and un- 
yielding nature of its materials, and its fibrous arrangement. It is 
most commonly employed in fastening the bones to each other at 
their articulations, in enveloping the muscles, in connecting the lat- 
ter, by tendon, to the skeleton, and in completing them, but it is 
also used in many other ways. Its application in the formation of 
the joints is our present object, but before that is particularly noted, 

* Anat. Atlas, Figs. 98, 99. 



288 



SKELETON. 



it "will be useful to enter into some general considerations in regard 
to its intimate structure, and the observations now made can be ap- 
plied on all other occasions when this tissue is in question. 

A desire to generalize, and consequently to simplify, has induced 
anatomists to seek for some fountain or source from which all the 
reflections and applications of the desmoid tissue might be traced. 
The Arabians thought that the dura mater was this source ; and the 
error' was sanctioned for a long time by the authority of Sylvius. 
The celebrated Bichat, in observing the connexions of this tissue, 
finding that all its points of application might be traced either medi- 
ately or directly to the periosteum, considered the latter as its 
centre, as the heart is the centre of the circulation, and the brain of 
nervous energy ; not that he thought the periosteum radiated its in- 
fluence on all its dependent organs, but because anatomical inspec- 
tion demonstrated all the fibrous organs to be connected with it, and 
communicating through it with each other. The late Professor 
Bonn, of Amsterdam, reversed the idea of Bichat, and considered 
the aponeuroses of the extremities, and of the trunk, which send 
their partitions between the muscles, and down to the periosteum 
and joints, as the much desired centre of the desmoid system. The 
latter idea has been reiterated by others, and the supposed emana- 
tions from the superficial aponeuroses diligently traced. As means 
of studying the position and connexions of parts, notwithstanding 
the construction is a very forced one, which makes desmoid tissue 
cellular membrane, and cellular membrane desmoid tissue, alter- 
nately, so as to suit the arrangement of the anatomist, instead of 
that of nature; yet, any or all of these plans have their use, and may 
be followed advantageously, after the study at large of the human 
■ fabric. 

The desmoid tissue is essentially fibrous, but without a uniform 
arrangement, as its fibres are either parallel, crossed or mixed. In 
some places the fibres are very compact, and separate with difficulty, 
but generally prolonged maceration will cause them to part into 
filaments as fine as the thread of the silk-worm. Anatomists differ 
in regard to the ultimate structure of these fibres. By M. Chaussier 
they are thought to be primitive and peculiar ; Mascagni* supposed 
that they were lymphatics, enclosed in a vascular web ; Isenfiam, 
that they were cellular substance imbued with gluten and albumen. 

* Prodomo della Grande Anatomia. 



LIGAMENTOUS TISSUE. 289 

And M. Beclard, observing that maceration resolves them into a 
species of mucous or cellular substance, teaches that they are the 
latter in a condensed state. Bichat's opinion is probably correct 
that the tissue is peculiar, and that maceration only brings into view 
the cellular substance which unites its fibres. Though maceration 
and chemical management evolve some striking coincidences with 
cellular membrane, yet in the natural and ordinary state there are 
some very strong points of difference from it. Among these may be 
remarked its great want of elastictiy, which causes it to tear sooner 
than to stretch ; and in general anasarca, its being only very parti- 
ally affected, merely rendered a little more moist and humid, which 
even then may arise from the small quantity of cellular substance in 
it. Many parts of it, however, are unaffected in the latter way, as 
the tendons and their sheaths. This tissue naturally contains a con- 
siderable quantity of water, which it loses by exposure to the air ; 
it then is much reduced, and becomes hard and yellowish, and is 
made semi-transparent by being put into spirits of turpentine. 

The fibrous tissue according to the present state of microscopical 
anatomy, consists of ultimate transparent undulating filaments, 
having a diameter from the ^fan to the ix >,h^ of an inch. The 
fasciculi into which they are collected, measure from the ? it.(j to the 
3,tW of an inch broad, and have their ultimate filaments held together 
by an amorphous substance called the cytoblastema. The ultimate 
fibres appear to be identical in fibrous, fibro-cellular, and cellular tissue. 
The more obvious differences arise from the mechanical apposition 
of the ultimate filaments, whether they are parallel or interwoven, or 
a combination of the two. If the fasciculi be absolutely straight, 
but a very small elasticity exists, as in the case of tendons amount- 
ing to almost nothing ; but in the case of some of the ligaments, as 
the yellow ones of the spine, the inter-texture of their filaments and- 
fasciculi imparts a high degree of elasticity. Like a muslin ban- 
dage, which if torn out straight, yields but little, and if cut bias, 
then is highly elastic, a modification of property highly applicable in 
certain surgical dressings. 

The desmoid tissue, by being subjected to the heat of boiling 
water, contracts, becomes more solid, and is elastic; but if it be 
continued there, it gradually softens, becomes semi-transparent, and 
gelatinous. The mineral acids reduce it to a pulpy state, and 
if concentrated, will dissolve it entirely. The alkalis loosen its 
texture, cause the fibres to separate easily, and to assume a diver- 

Vol. I.— 25 



290 



SKELETON. 



sity of colours. It putrefies but slowly, in this respect being next 
to the cartilages. 

The strength of this texture is remarkable, and adapts it to the 
sustaining of enormous weights ; a faculty which is continually in 
requisition, both to retain the articular surfaces of bones in contact, 
and the muscles and tendons in their places. It is well known 
that the patella, the olecranon, and the os calcis, break frequently 
before their tendinous attachments will give way. In the history 
of punishments, where criminals have been fastened to four horses, 
it is said that it has been found necessary to use a knife to assist in 
their disarticulation. All these phenomena occur when abrupt 
violence is resorted to, so little are the ligaments disposed to yield ; 
but when the causes of distention act slowly and gradually, as in 
dropsies of the joints, the fibres separate, and are sometimes com- 
pletely disunited. When the distending cause ceases to operate in 
the latter case, the ligaments have the power of contracting in the 
same gradual way, and of restoring themselves. 

Some of the desmoid tissues, besides having their fibres sur- 
rounded and their interstices occupied by cellular substance, con- 
tain a very small quantity of oily or fatty matter. This is not very 
obvious in their recent state ; but, by drying them, it will be seen 
in small quantities on their surface, like a greasy exudation: this 
probably comes from the cellular substance in them. They are 
furnished but sparingly with blood vessels, which for the most part, 
are capillary. The periosteum and the dura mater are, however, 
exceptions to this rule. Lymphatic vessels have been observed in 
some of them, but it is doubtful whether they generally have nerves.* 

S. Pappenheim has asserted that in his dissections he has been 
able to trace nervous filaments, in the periosteum, in ordinary liga- 
ments, in capsular ligaments, and sometimes in the tendons but 
not those of the human subject. They invariably attend the blood 
vessels of these parts respectively and end in terminal loops. f 

The sensibility of this system is extremely obscure, and is not 
manifested under the usual mechanical and chemical irritants; it 
may, however, be elicited by communicating to the joints a twist- 
ing motion, as the experiments of Bichat prove. Inflammation aug- 
ments their sensibility, in which case it becomes extremely acute, 
as in gout and rheumatism, or any other cause productive of it. 

* Beclard, Anat. Gen. f Mailer's Arch. 1843. 



SYNOVIAL ARTICULAR CAPSULES. 291 



SECT. II. — OF THE LIGAMENTS OF THE JOTNTS. 

The Ligaments, (Ligamenta,)' 'properly speaking, are those organs 
which tie the bones together, and in the moveable joints are either 
Capsular (capsules fibreux) or Funicular, {ligamens fibreux fascicu- 
laires.) The first are like a bag open at the ends, at either of 
which the articular extremity of a bone is included. These are 
much more complete in some joints than in others; the shoulder 
and the hip joints afford the most perfect examples; in other joints 
they are divided into irregular fasciculi of fibres, permitting the 
synovial membrane to appear in their interstices, and sometimes 
they are still more widely separated. 

The funicular ligaments are mere cords, extending from one bone 
to another; some of them are flattened, some rounded, and others 
oval or cylindroid. They are variously placed; in some instances 
they are within the capsular ligament, and in others, on its outer 
surface, and sometimes so blended with it as not to be separated 
without an artificial dissection. Their names are derived either from 
their position or shape, and are generally sufficiently appropriate. 



SECT. III. OF THE SYNOVIAL ARTICULAR CAPSULES. 

Each moveable articulation is lined by a membrane, (Membrana 
Synovialis,) reflected over the internal face of the capsular ligament 
and the articular cartilages. This membrane is a perfect sac; and 
unlike the capsular ligament, has no opening in it. It is remarka- 
bly distinct where it is not attached to the articular cartilages; and, 
by being inflated, is caused to protrude in small vesicles, or pouches, 
between the fasciculi of the ligamentous structure. Its connexion 
with the cartilage, and its continuation over it, are not quite so 
obvious, and require more management to demonstrate : it is, indeed, 
so thin and transparent at this part, and adheres so closely, that its 
existence there has been questioned, but maybe proved in a variety 
of ways. By maceration it becomes so loose, that, with a pair of 
forceps, shreds of it may be raised along the whole extent of the 
cartilage. If a flap of cartilage be raised up by a knife, its base 
being left attached, in attempting to tear away the base it will be 
found that the synovial membrane is continued from this base to the 
contiguous cartilage. Saw a bone through to its articular cartilage, 



292 



SKELETON. 



then tear through the cartilage gently, in which case the continuity 
of the synovial membrane will also be manifested. 

From these several proofs the fact is established, that the syno- 
vial membranes are bags, closed at both extremities, and differ 
thereby from the capsular ligaments. 

The synovial sacs are very vascular except upon the articular 
cartilages where the vascularity is no longer apparent, or advances 
but a very short distance. M. Beclard says, that protracted inflam- 
mation will, finally, redden the cartilaginous portion, and that it 
extends from the circumference to the centre, the hues being lighter 
the nearer it is to the latter. It has not occurred to me to meet 
with this proof; though I have made frequent dissections of inflamed 
joints, on subjects, the redness has always ceased at the margin of 
the articular cartilage. Dr. Physick's experience, most valuable 
on all occasions, affords support to my own. — Some years ago I had 
an opportunity of investigating, somewhat fully, this point, in a 
subject, all of whose large joints were in a state of inflammation. 

The following magnified plate, of the head of the os femoris, at 
from the third to the fourth month of fcetal life, will represent the 
very partial advance of vascularity between the synovial membrane 
and the articular cartilage. 



Fig. 4. 




a, the surface of tlic articular cartilage, near the ligamentum teres; 6, the vessels 
between the said cartilage and the synovial membrane ; c, the surface where the 
IJgamentum teres was attached; d, the vein; e, the artery. 

These synovial capsules, or membranes, are white, thin, semi- 
transparent, and soft. Wherever there is a deficiency of capsular 
ligament, they adhere to the contiguous cellular substance, and are 



SYNOVIAL ARTICULAR CAPSULES. 293 

so blended with it as to appear absolutely continuous. Dissection, 
inflation, and maceration, prove them to be laminated, and deve- 
lope their structure in such a way that it resolves itself into a cellular 
tissue, the more interior layers of which had been in a very com- 
pacted state. In all this they resemble the serous membranes, 
generally, and are ranked among them; Bichat, therefore, considers 
them only as an interlacement of absorbents, and of exhalants. 
But, for the farther exposition of this point, see the article on the 
Serous Membranes. 

The synovial sacs have, on their outer surface, but projecting 
into the cavity of the joint, adipose cushions of different sizes, 
called the Synovial Glands of Havers/from which, it was long sup- 
posed that the lubricating liquor of the joints is exclusively secreted. 
These cushions have their projecting margins fringed and unusually- 
vascular, and occupy the small spaces left between the articular 
faces of the bones. As they are covered by the synovial membrane, 
they no doubt assist in the secretion of the synovia. 

The moveable articulations are all furnished with the fluid called 
Synovia; this name was given to it by Paracelsus, from its resem- 
blance to the albuminous part of an egg, to the consistence and 
colour of which it has a close affinity, and, like it, is thick, ropy, 
and somewhat yellowish. The chemical analysis of it indicates 
the presence of water, albumen, and a kind of incoagulable mucus. 
It was once supposed to be a mixture of serum, with the adipose 
matter of the bones, which found its way into the joints by trans- 
udation ; but as it contains upon experiment no oil, the opinion is 
evidently erroneous. It is secreted from the whole internal ^surface 
of the synovial membrane, and, perhaps, in greater quantities from 
the fringed fatty cushions in the joints in consequence of their in- 
creased vascularity. M. Beclard teaches, that it is neither a 
follicular nor a glandular secretion, nor a transudation, but a per- 
spiration, in which a perfect equilibrium is kept up between its 
exhalation and its absorption. Its use is to diminish friction, and, 
consequently, to facilitate the sliding of the bones upon each other. 

The synovial capsules are liable to a fungous degeneration which 
occurs equally upon the cartilaginous and capsular portions of them, 
Factitious bridles sometimes form in the joints, attached indiscrimi* 
nately to either portion of the synovial membrane. 

25* 



294 SKELETON. 



CHAPTER IV. 

Articulation of the Lower Jaw.* 

The articular connexion, here is formed by that portion of the 
glenoid cavity anterior to the fissure, and 'by the condyle of the 
lower jaw. Each surface is covered by thin cartilage ; and a thin, 
loose, irregular, fibrous, capsular ligament, arises from the articular 
margin of one bone, to be inserted into that of the other. Besides 
this, there are four other ligaments for strengthening the joint, an 
inter-articular cartilage, and two synovial membranes. 

The External Ligament (Membrana Articularis Ligamentosa) 
arises from the inferior margin of the root of the jugal or zygomatic 
process of the temporal bone, and from the anterior side of the 
meatus externus, and is inserted into the neck of the condyloid process. 
It is somewhat triangular, having the base upwards, and is identified 
with the capsular ligament. Just in advance of this, and separated 
from it by a small fissure, is another triangular ligament, the dis- 
covery of which is claimed by Caldani.f It arises from the ante- 
rior part of the inferior margin of the zygomatic process of the tem- 
poral bone, and is inserted into the neck of the bone in advance of 
the other. 

The Internal ligament (Lig. Maxilla Later ale) or Spino-maxillary, 
arises from the extremity of the spinous process of the sphenoid bone, 
and from the adjoining part of the processus vaginalis of the tem- 
poral bone, and going downwards and outwards, is inserted into the 
spine bordering the posterior mental foramen, and for some distance 
lower down on the ramus of the jaw. It is placed between the two 
pterygoid muscles, and is in contact with the maxillary vessels and 
nerves, as they run between it and the condyle to the posterior men- 
tal foramen. It is thought by Caldani to be not so useful in restrict- 
ing the motion of the jaw forwards, as in holding the vessels and 

* Anat. Atlas, Figs. 100, 101, 102. 
f Tabul. Anat. Venetiis, 1802. 



ARTICULATION OF THE LOWER JAW. 295 

nerves, and regulating their position, lest in the various motions of 
the lower jaw they should be displaced and injured. 

The Stylo-maxillary Ligament is thinner than the above. It 
arises from the external side of the styloid process, and is inserted 
into the posterior margin of the jaw, near its angle, between the 
masseter and internal pterygoid muscles. The stylo-glossus muscle 
is much connected with it, and is thereby assisted in elevating the 
base of the tongue, the fascia profunda of the neck is in continua- 
tion with it. 

There are two synovial membranes, the one reflected between the 
glenoid cavity and the upper surface of the inter-articular cartilage, 
and the other between this latter substance and the condyle of the 
lower jaw. They may be seen at different points protruding be* 
tween the fibres of the capsular ligament. 

The Inter-articular cartilage, by being placed between the two 
synovial membranes, separates completely the two bones. Above, 
its surface corresponds to the convexity of the tubercle of the tem- 
poral bone, and to the glenoid cavity ; below, it is simply concave 
for receiving the condyle. It is thicker at the circumference than 
in its middle, and at the posterior than the anterior margin. A 
longitudinal section of it, from before backwards and near its mid- 
dle resembles the letter S. Sometimes it is open in the centre, in 
which case the two synovial cavities run into one another. Its 
structure is fibro-cartilaginous. It moves very readily backwards 
and forwards. 

On the posterior face of the capsular ligament, I have found, in 
several cases, indeed, on all occasions of special examination for it, 
since the first observation, an erectile tissue or structure resembling 
the corpus cavernosum penis. It has not been filled with blood 
like the latter, but is, probably, an arrangement for giving great 
mobility forwards, to the lower jaw. 

The movements of this bone may be simply hinge-like, by its 
depression, in which the mouth is regularly opened; or, by the ac- 
tion of the pterygoid muscles, it may be slid forwards. When the 
muscles of but one side act, a species of rotation is communicated ; 



296 



SKELETON. 



in which one condyle advances on the tubercle of the temporal bone, 
while the other reaches to the back part of the glenoid cavity. The 
looseness and length of the capsular ligament of the articulation, 
along with the extreme facility of motion from the interposition of a 
moveable cartilage, contribute very materially to this movement. 
The sliding backwards and forwards of the intermediate cartilage of 
this articulation, during mastication, sometimes produces a crackling ; 
audible to the by-standers, and extremely annoying to the individual 
who is the subject of it, from the noise being so near his ear. 

Some persons are liable to a spontaneous dislocation of this bone, 
from yawning too widely. I am disposed to believe, that, in such 
cases the accident arises from the posterior boundary of the glenoid 
cavity, (as established by that margin of the temporal bone which is 
continuous with the vaginal process, and forms a part of the meatus 
externus,) being more advanced and higher than usual ; in conse- 
quence of which, whenever the bone is depressed to a certain point, 
its neck strikes against this ridge, and not being able to go farther 
back, the ridge acts as a fulcrum, and starts the condyle over the 
tubercle of the temporal bone into the zygomatic fossa. The fact 
is certain, that very strongly marked differences of the glenoid ca- 
vity, in this particular, occur in different individuals. 



CHAPTER V. 
Of the Ligaments of the Spine. 

Ligaments of the Bodies of the Vertebra* 

1. Inter-vertebral Substance, (Ligamenta Intervertebralia, Liga- 
mens Inter vertebraux.) — The bodies of the true vertebra? are united 
by a substance blending the nature of ligament and that of cartilage, 
and therefore, called fibro or ligamento-cartilaginous matter. It 
occupies all the space between the contiguous bodies of the verte- 
brae, and adheres most closely to their substance. This inter-ver- 
tebral matter increases successively in thickness, as it is placed lower 

* Anat. Alas, Figs. 103, 101. 



LIGAMENTS OF THE SPINE. 297 

down on the spine, whereby the lumbar vertebrae are mutually at a 
much greater distance than any others. The curvatures of the spine, 
as formerly stated, depend considerably upon the arrangement of this 
substance : between the vertebrae of the neck it is thicker at its an- 
terior margin than at the posterior ; on the contrary, between the 
dorsal vertebrae it is thinner in front. In the loins, it is again much 
thicker in front than behind, and this feature is unusually marked 
between the last lumbar vertebra and the sacrum. 

This inter-vertebral matter is formed of concentric lamellae, the 
texture of which is ligamentous. These lamellae are more abundant 
anteriorly and laterally than behind. Their fibres cross in every di- 
rection, leaving between them interstices or cells, filled with a soft, 
pulpy substance : this substance is not very obvious near the cir- 
cumference, but in approaching the centre, it becomes more and 
more abundant, as the interstices are larger, until the centre seems 
to be constituted almost entirely by it. The pulpy mass in the 
centre is in a state of considerable compression, which may be 
proved by separating the bodies of adjoining vertebrae, or by making 
a vertical section through them. ; in which case the pulpy mass will 
be freed from compression, and will rise up into the form of a cone. 
This experiment will succeed remarkably well in the loins ; from 
which it is evident, that this mass is a soft and elastic ball, on which 
the bodies of the vertebrae play. 

If the circumference of the inter-vertebral plate, be cut through 
in the plane of its attachment to the vertebra, and the joint then 
forced open, it will be found, that the strongest adhesion had been 
at the plane of the circumference, for the surfaces within, part with 
comparative ease, and a thin scale or plate of cartilage, will be 
found adhering to the face of the vertebra, and concealing it. This 
plate is probably the last vestige of the epiphysis of the vertebra. 

The pulpy matter is proportionably much more abundant in in- 
fancy than in the subsequent periods of life ; it is also much softer, 
whiter, and more transparent. In advanced life there is great dimi- 
nution of its volume, as well as of its elasticity, which accounts, in 
some measure, for the comparative stiffness of the spine in old 
people. The fibrous part in them is always more abundant, and 
is much disposed to ossify. When the trunk is kept erect for se- 
veral hours in succession, it becomes shorter, from its weight bear- 
ing upon the inter-vertebral mass ; but a short period of rest in the 
horizontal position, restores it to its original length. 



298 

^° SKELETON. 

2. Anterior Vertebral Ligament, (Fascia Longitudinalis Anterior, 
Ligament Vertebral Merieur. }^-This ligament is placed on the front 
part of the spine, and extends from the second vertebra of the neck 
to the first bone of the sacrum, inclusively. It increases gradually 
in breadth, from its commencement to its termination, but is not 
every where of the same thickness ; for it is thin on the neck, thicker 
in the thorax, and again becomes thin in the loins: in the latter 
however, it is strengthened by an accession of fibres from the tendi- 
nous crura of the diaphragm. 

This ligament adheres very closely to the inter-vertebral sub- 
stances, or plates, and to the projecting margins of the bodies of the 
vertebra;, but less closely to the middle or concave parts of the 
latter. Its fibres do not run out its whole length, for the more 
superficial extend from one vertebra, or inter- vertebral substance, 
to the fourth or fifth below: the middle ones extend to the second 
or third below; and the deepest seated are applied between the 
proximate vertebra? only. In general, more of the fibres are inserted 
into, and arise from the fibro-cartilaginous matter than the bones. 
In several parts, but particularly in the neck, small slips are sent off 
obliquely to the vertebra below. The laminse of this ligament 
leave intervals between them for the passage of blood vessels. 

Beneath the anterior vertebral ligament are found a great many 
short and insulated ligamentous fibres, extended obliquely from one 
vertebra, to another which is contiguous. These fibres have diffe- 
rent directions, and cross each other at acute angles; they adhere 
very closely to the fibro-cartilaginous matter, and leave interstices 
between themselv r es, through which the anterior vertebral ligament 
adheres to the same substance. Moreover, there are at the sides 
of the bodies of the vertebra?, a number of short straight fibres, 
passing from the edge of the bone above to the edge of the bone 
below. 

3. Posterior Vertebral Ligament, (Ligamenium Commune Poste- 
rius, Ligament Vertebral Posterieur.) — This is placed on the hind 
part of the bodies of the vertebras, within the spinal canal, and ex- 
tends from the cuneiform process of the occiput just beyond the 
foramen magnum, to the os coccygis. It is more narrow and thick 
in the thoracic vertebra? than elsewhere. At each inter-vertebral 
substance it increases in breadth and adheres more closely, whereas, 
opposite the body of a vertebra it is narrower and more loose, 



LIGAMENTS OF THE SPIXE. 299 

by which arrangement a kind of serrated or unequal edge is formed 
on each side. 

This ligament is more dense and compact than the anterior and 
presents a smooth, shining surface, resembling a tendinous expan- 
sion. Its fibres, also, do not run individually the whole length 
of the spine, but are in lamina? ; the more superficial of which have 
their fibres inserted into the fourth or fifth inter- vertebral substance 
or vertebra, below their origin. The middle laminae are inserted 
into the second or third below, and the deeply seated into the first 
below. The blood vessels do not penetrate the ligament, but pass 
by its sides into the vertebras. The superior extremity of this liga- 
ment going from the second vertebra to the margin of the foramen 
magnum, is sometimes considered as distinct. 



Ligaments of the Processes of the Vertebra. 

1. Articulation of the Oblique Processes.— These processes are 
faced with cartilage, and a synovial capsule is displayed upon them 
so as to shut up completely the cavity of the articulation. The 
capsular ligament is not uniform and fully developed, but is repre- 
sented by a few irregular fibres, passing from one bone to the 
other. 

2. Articulation of the Spinous Processes. — With the exception of 
the neck, ligamentous fibres are found to occupy the spaces between 
all the spinous processes, by passing their whole length from the 
spinous process above, to the spinous process below. Muscles 
supply largely their places in the neck, and to some degree in the 
upper part of the thorax. These ligaments have much of a cellular 
structure above, but in their descent they become more ligamentous 
and large, till, in the loins, they assume a very decided character, 
and have a quadrilateral shape. 

At the extremities of the spinous processes there is, also, a liga- 
mentous band, belonging to the dorsal and lumbar vertebras; com- 
mencing at the seventh cervical, in connexion with the Ligamentum 
Nucha?, it terminates on the spinous processes of the sacrum. It is 
thin in the back, but on the loins it is very thick, and so blended 
with the tendinous origins of the muscles, that it is not very dis- 
tinguishable from them. The fibres of which it consists are of un- 



^0 SKELETON. 

equal lengths, being extended between two, three, four or live 
vertebrae, accordingly as the fibres are superficial or deep-seated. 

3. Owing to the shortness of the spinous processes of the neck, 
an arrangement exists there called Ligamentum Nuchas, {Ligament 
Cervical,) or the Descending Ligament of Diemerbroeck. This 
ligament, though continuous with the one last described, may be 
considered, for the sake of perspicuity, as distinct. It begins, 
therefore, at the seventh cervical spinous process, ascends between 
the muscles of the opposite sides of the neck, and is inserted into the 
posterior occipital protuberance. It is blended very much with the 
tendons of muscles, and is distinguished from them with some dif- 
ficulty, occasionally. Its posterior margin is thick, but the anterior 
is a thin membranous expansion, which runs to the ends of the 
spinous processes of the cervical vertebras, and to the vertical 
ridge of the occipital bone, leading from the occipital protube- 
rance to the foramen magnum. The ligamentum nuchse, therefore, 
forms a complete septum between the muscles of the opposite sides 
of the neck, and is continuous with the sheaths in which they play. 
In quadrupeds it is remarkably strong, but in man, who from the 
proportions of his head and his erect position, keeps the head nearly 
in equilibrium, it is comparatively feeble. 

4. Articulation of the Bony Bridges of the Vertebra* — The in- 
tervals between the vertebrae, at the posterior part of the spinal canal, 
are filled up by the Yellow Ligaments, (Ligamenta Flava,) so 
called from their peculiar colour. These intervals exist between all 
the true vertebras, being bounded laterally by their oblique pro- 
cesses, and are very considerable in the loins, particularly that below 
the last vertebra ; they are not so large in the neck, and are still 
smaller in the back ; and their shape varies considerably in the 
several portions of the spine. 

The yellow ligaments are two in number, forming a pair, in each 
of these intervals : the two approach, behind, at an angle, in a line 
with the spinous processes, but are kept separated by a small ver- 
tical fissure filled up with cellular substance. They extend to the 
oblique processes laterally ; are connected to the anterior face of the 
bony bridge of the vertebra above ; whereas, they are inserted into 
the superior margin of that of the vertebra below. From this ar- 

* Anat. Atlas, Figs. 105, 106. 



LIGAMENTS OF THE SPINE. 301 

rangement, the yellow ligaments may be best seen on the side of the 
spinal canal. The angle which they form behind is continuous with 
the ligaments between the spinous processes. 

These yellow ligaments are smooth and shining on their anterior 
surfaces, but behind they are rough and unequal. Their fibres are 
numerous and extremely compact, their strength is, therefore, very 
great. Their elasticity is well marked and peculiar to them, and 
assists greatly in erecting the spine when it has been curved out of 
the proper line. Bichat says that there is but little cellular tissue 
between their fibres : that they are dissolved with extreme difficulty 
in boiling water, and resist its action to such a degree, that it is 
manifest they contain much less gelatin than the greater number of 
analogous organs. 

The first pair of yellow ligaments is between the second and third 
cervical vertebrae, and the last between the last lumbar and the 
sacrum ; there are, consequently, only twenty-three pairs in all. 



Particular Articulations of the Spine* 

1. Articulation of the Occiput with the Atlas. — The anterior Liga- 
ment is placed at the anterior part of the occipital foramen, and extends 
from it to the corresponding edge of the atlas. On its centre in front 
is a fasciculus, which being narrow and somewhat rounded, de- 
scends from the middle of the cuneiform process to terminate in the 
tubercle on the front of the atlas ; and consists in parallel fibres ; 
some of its fibres run into the anterior vertebral ligament. The re- 
mainder is called by Caldani, Membrana annuli anterioris atlantis, 
{Ligament occipito-atloidien anterieur.) It occupies and shuts up 
the whole space, between the basilar process of the os occipitis, 
from which it takes its origin near the occipital foramen ; and the ante- 
rior arch of the atlas, into the superior margin of which it is inserted. 
In it are many oblique fibres, which run from within outwards. 

The posterior Ligament is placed at the back part of the occipital 
foramen, and extends from it to the corresponding edge of the atlas. 
It is called by Caldani, Membrana annuli posterioris atlantis, 
[Ligament occipito-atloidien posterieur ;) and arising from the whole 

* Anat. Atlas, Figs. 107, 108^109, 110. 
Vol. I.— 26 



302 



SKELETON. 



posterior margin of the occipital foramen between the condyles, it is 
extended to the upper contiguous margin of the atlas, so as to fill 
up completely this space. Bichat says that it also consists in two 
laminse, the anterior of which is fibrous, and runs into the dura 
mater of the spine instead of into the bone : the posterior is of a 
much looser texture, and resembles common cellular substance. A 
part of this membrane runs obliquely from the transverse process of 
the atlas to the part of the occiput just beneath the insertion of the 
rectus posticus minor. 

The articulating surfaces of the condyles, and the superior ob- 
lique processes of the first vertebra, are covered with cartilage, and 
furnished with a synovial membrane arising from their margins. On 
the exterior of the synovial membrane there are irregular ligament- 
ous fibres going between the bones, and forming a capsule. 

2. Articulation of the second Vertebra with the Occiput, and with 
the first. — The second vertebra has no articular surface joining the 
occiput, but some strong ligaments are passed between them. 
When the posterior vertebral ligament is removed at its commence- 
ment from the occipital bone, we see on each side of it, and beneath 
it, ligamentous bands (Lacerti Ligamentosi,) coming from the in- 
ternal face of the os occipitis, to be affixed to the body of the second 
vertebra behind. Some of these fibres arise from the margin of the 
occipital foramen, and others from the internal face of the condyloid 
processes.* They are joined at their external margins by a few 
fibres from the first vertebra, near its upper oblique process. 

The Transverse Ligament (Ligamentum Transversale Atlantis, Li- 
gament Transversal,) is placed immediately behind the processus den- 
tatus, and divides the atlas into two unequal rings by being stretched 
from one side to the other. It is larger in the middle than at the 
extremities, and has the latter inserted into the little tubercle at the 
internal side of the atlas, between the upper and the lower articular 
surfaces. It is a thick, strong fasciculus of fibres, and binds the 
processus dentatus so as to form for it a sort of collar, amounting to 
about one-fourth of a circle. The superior appendix of this ligament 
arises by a broad base from the anterior margin of the foramen mag- 

* Caldani, Icon. Anat. Explicatio, vol. i. p. 255. 



LIGAMENTS OF THE SPINE. 303 

num, and terminates below by a narrow end in the upper margin of 
the transverse ligament. The inferior appendix arises from the 
lower edge of the transverse ligament, and is attached, by a some- 
what converging end, into the posterior face of the body of the ver- 
tebra dentata. 

The surfaces of contact belonging to the processus dentatus, and 
to the anterior ring of the atlas, are covered with cartilage, and have 
a synovial membrane, so as to form a perfect joint called the Va- 
ginal ligament. A joint with a distinct synovial membrane is, in 
like manner, formed between the posterior face of the processus 
dentatus and the anterior of the transverse ligament, where they come 
into contact. 

The Oblique or Moderator Ligaments {Lig. Lateralia, Ligamens 
Odontoidiens) are two, one on either side of the tooth-like process. 
They may be seen most advantageously by cutting through the 
transverse ligament, and arise from the side and summit of the pro- 
cessus dentatus, to be inserted into the internal margin of the occi- 
pital condyle. They are thick, short, and strong, and consist in 
parallel fibres ; their lower margin has been considered as a distinct 
ligament by Weitbrecht, and described by him as coming from the 
neck of the process. There is some cellular tissue at the front, in 
which the process revolves. 

The Middle Straight Ligament, {Lig. Medium Rectum, Ligament 
droit Moyen,) or Occipito-Dentate, arises from all that part of the 
summit of the processus dentatus anteriorly which is between the 
moderator ligaments, and is inserted into all that part of the interior 
circumference of the foramen magnum between the insertion of the 
moderator ligaments. It is a thin ligamentous membrane, disposed 
to form in its middle a vertical fissure, separating its two halves. It 
cannot be seen well, unless the whole membrana annuli anterioris be 
dissected away, and the anterior bridge of the first vertebra sawed 
off; it will then be found immediately behind the bursa or vaginal 
ligament of the processus dentatus. It is separated from the supe- 
rior appendix of the transverse ligament by a layer of condensed 
fatty substance. This ligament should not be confounded with the 
superior appendix of the transverse ligament, nor with the beginning 
of the posterior vertebral ligament as has been done by Bichat and 
others. The difference is well established by Caldani, as it lies 



304 



SKELETON. 



deeper than either of them when viewed from the vertebral cavity ; 
though, from the close connexion of the fibres of the ligaments 
among themselves, as well as with others, the mistake may readily 
occur.* 

The Articulation between the oblique process of the first and of 
the second cervical vertebra is very moveable, as the atlas is per- 
mitted to revolve around the processus dentatus to the amount of 
one-fourth of a circle at least. This articulation has a synovial 
capsule which is strengthened by an anterior and by a posterior 
ligament. 

The anterior ligament of the articulation between the oblique 
processes arises from the inferior margin of the atlas and from its 
anterior tubercle, and is inserted into the base of the processus 
dentatus, and into the front of the body of the second vertebra. 
The fibres of the latter insertion are long and frequently distinct 
from the first. 

The posterior ligament is placed between the first and second 
vertcbroe behind, and is connected to their contiguous margins so 
as to fill up the interval between them, and to supply the place of 
the yellow ligaments. It is extremely loose and thin, so as not to 
interfere in the movements of the vertebra, and is almost of a cel- 
lular structure. 

The synovial membrane of these oblique processes is unusually 
lax, and is reflected from the margin of the one articular surface to 
the other. It is in contact in front with the anterior ligament; behind 
with the posterior and with much cellular substance ; internally 
with the ligaments within the spinal canal, and externally with the 
carotid artery. The latter obtains from it a serous covering, with- 
out which, according to Bichat, it would be bathed in the synovial 
fluid. 

* Its existence is, however, scarcely to be considered uniform, as itis often 
wanting where the processus dentatus is very long, for example, when it 
reaches the anterior part of the foramen magnum and forms a joint there, as it 
sometimes does. 



LIGAMENTS OF THE PELVIS. 305 



CHAPTER VI. 

Of the Ligaments of the Pelvis.* 

The mode of junction between the sacrum and the last lumbar 
vertebra, is, in every respect, the same as that described for the 
bones of the spine generally, with the addition of a ligament on 
each side, sometimes met with, called Sacro- vertebral, which arises 
from the superior part of the sacrum by blending itself with the 
anterior fibres of the sacro-iliac junction, and going obliquely up- 
wards, is inserted into the transverse process of the last lumbar 
vertebra. 

The Sacrum is united to the coccyx by a fibro-cartilaginous sub- 
stance, resembling that between the bodies of the true vertebras, 
with the exception of there being less pulpy matter in its centre, 
and of its fibrous lamellee being more uniform. The bones of the 
coccyx are also united with one another in the same way; in 
consequence of which they are very flexible till the approach of 
old age. 

The Anterior Coccygeal Ligament, {Lig. Sacro-coccygeum Jlnte- 
rius) is placed on the forepart of the coccyx; runs its whole length, 
and arises from the inferior extremity of the sacrum. Its fibres are 
rather indistinct, from their being blended with fat; on the lateral 
margins of the coccyx they are better marked. 

The Posterior Coccygeal Ligament, {Lig. Sacro-coccygeum Pos- 
terius,) as its name implies, is placed on the back part of the coccyx. 
It arises from the inferior margin of the spinal canal of the sacrum, 
and forms a sort of membranous expansion, which covers and 
adheres to the first bone of the coccyx, and is also inserted into the 
second. There are also a few other ligamentous fibres connecting 
the bones of the coccyx. 

* Anat. Atlas, Figs. Ill, 112. 
26* 



306 



SKELETON. 



The Ilio Lumbar Ligament (Lig. Rio Lumbare) arises from the 
crista of the ilium for two inches near the lumbar vertebra;, and 
passing inwards is inserted into transverse process of the last lumbar 
vertebra, and into its inferior oblique process. It is often blended 
with adipose matter, which separates it into several fasciculi. 
Caldani describes it as two ligaments, making a distinction between 
the one part fixed to the transverse, and the other to the oblique 
process. 

The Sacro-Iliac Articulation is formed by the corresponding sur- 
faces of the sacrum and ilium. Each bone is incrusted with its own 
cartilage, the one on the sacrum being somewhat more thick. Their 
surfaces are slightly rough, and between them exists a thick yellow 
fluid in a very small quantity, which lubricates them, and is more 
abundant in early life. 

The Sacro-spinous Ligament {Lig. Sacro-Spinosum) is placed 
superficially on this articulation behind. It is very strong, flat, 
long, and perpendicular. It consists of two laminae, of which the 
more superficial arises from the fourth transverse process of the 
sacrum, and is inserted into the posterior superior spinous process of 
die ilium. The deep-seated lamina arises from the third transverse 
process of the sacrum, and is inserted into the same point. Bichat 
describes, connected with the inferior margin of this ligament, a fas- 
ciculus, which adheres to the posterior inferior spinous process of 
the ilium. 

The Sacro-Iliac Ligament (Lig. Sacro-lliacum) is next to the 
articular faces of the bones. It surrounds the joint, but is much 
stronger on its posterior face. It consists in an assemblage of liga- 
mentous fasciculi, some of which have obtained, by the writers on Syn- 
desmology, particular names, but which it would scarcely add to the 
student's information to designate. On the front of the joint this 
ligament is uniform, and consists of a plane of short, strong fibres, 
passing from the margin of one bone to that of the other. But, on 
the posterior surface, it is much more irregular, and arises from the 
first tvvo eminences near the lateral margin of the sacrum, corre- 
sponding with the transverse processes of the true vertebrae, and from 
that surface of the sacrum between these eminences and its articular 
face. From thence the sacro-iliac ligament goes to be inserted into 



LIGAMENTS OF THE PELVIS. 307 

the rough surface of the ilium, immediately behind its articular face ; 
it fills up there a considerable space, and, from its position, must be 
extremely irregular. Its strength, is so great, that in forcing the 
joint the ligament does not rupture, but parts preferably from 
the surface of the ilium, and sometimes brings with it a lamella of 
bone. 

The bones of the pelvis are also fastened by two other very strong 
ligaments, the sacro-sciatic. 

The Posterior Sacro-Sciatic (Lig. Sacro-Ischiadicum majus) is the 
most considerable of the two. It arises from the posterior inferior 
spinous process of the ilium, from the margin of the sacrum below 
this bone, and somewhat from its posterior surface, and from the 
first bone of the coccyx. It goes downwards and outwards, be- 
comes thicker in its middle, but narrow ; it then spreads out, and is 
inserted along the internal margin of the tuberosity of the ischium. 
Its anterior extremity is extended along the internal face of the eras 
of the ischium for some distance, and has the obturator internus 
muscle adhering to it. Its fibres, where they converge from their 
origin, are separated into planes by bits of fat, and by blood 
vessels. 

The Anterior Sacro-Sciatic Ligament (Lig. Sacro-Ischiadicum 
minus) is much smaller than the other, and is placed in front of it. 
It arises from the margin, and somewhat from the posterior surface 
of the sacrum, below the ilium ; and from the lateral margin of all 
the bones of the coccyx. The fibres converge, and are inserted into 
the spinous process of the ischium, by embracing it. The fibres 
constituting its base, have their fasciculi separated by cellular adi- 
pose matter and by vessels, and are also intermingled with the fibres 
of the coccygeus muscle, and of the posterior sacro-sciatic liga- 
ment. 

The two sacro-sciatic ligaments supply, in some degree, the place 
of bone, and form a part of the inferior lateral parietes of the pelvis. 
They convert the sciatic notch into a foramen, or, rather, form with 
it two foramina; the upper and larger of which transmits the pyri- 
formis muscle, the sciatic nerve, and the gluteal blood vessels ; 
while the lower, placed betw r een the insertion of the two ligaments, 
transmits the obturator internus muscle, and brings the internal 
pudic artery into the pelvis. 



308 



SKELETON. 



The Obturator Ligament (Membrana Obturatoria) is extended 
across the foramen thyroideum, so as to close it up, with the ex- 
ception of a foramen at its upper part, for transmitting the obturator 
vessels and nerves. It is a thin, but strong membrane, having its 
fasciculi of fibres passing in various directions, and arising from 
the margin of the foramen. It affords origin to many of the fibres 
of the obturator muscles. Frequently portions of it are very de- 
fective. 

The Articulation or Symphysis of the Pubes is formed between 
the bodies of the two ossa pubis. It consists principally in a fibro- 
cartilaginous matter, which has a strong resemblance to that of the 
vertebrae. When the bones are torn apart by bending them for- 
wards, the fibrous arrangement becomes very apparent, and is seen 
to consist in concentric lamellae, the fibres of which cross one 
another. Sometimes in the male, but most frequently in the female, 
the posterior third of the articulation is deprived of these fibres, in 
place of which we find, in the middle of the cartilage, a small lon- 
gitudinal cavity, the surface of which is smeared with a kind of 
mucosity. There is no central pulpy matter in this articulation, as 
there is between the vertebras. On its posterior surface it often 
makes a ridge projecting into the cavity of the pelvis. From fre- 
quent observations made in our dissecting-rooms, I have no doubt 
that this articulation is always very much relaxed in the parturient 
and pregnant female, which is manifested not by the bones separating, 
but by their sliding upwards and downwards with great readiness. 
The sacro-iliac junction also becomes relaxed. It was upon the 
observation of these facts, that the celebrated, but now exploded, 
Sigaultian operation was founded. 

The Anterior Pubic ligament is not very distinct. It lies in front 
of the last articulation, and consists in a few oblique and transverse 
fibres going from the one bone to the other. 

The Sub or Inter-Pubic Ligament (Lig. Pubis Inferius) occu- 
pies the summit of the arch of the pelvis. It is of a triangular 
form, about half an inch in breadth, and passes from the margin of 
the crus of the pubes of the one side, to a corresponding line on the 
other. It is remarkably strong, and is rather more so below than 



ARTICULATIONS OF THE THORAX. 309 

above. It seems rather an extension of the ligament of the sym- 
physis pubis, than a distinct structure. 



CHAPTER VII. 



Articulations of the Thorax. 

Posterior Articulations of the Ribs* 

As mentioned, in the account of the bones, the articulations here 
are double ; being formed at one point between the heads of the 
ribs and the bodies of the vertebras with the inter- vertebral matter ; 
and at the other, between the tubercles of the ribs and the transverse 
processes. In either case the respective surfaces are covered by 
articular cartilage, and have a synovial membrane. The first joint 
is the Costo-vertebral, and the second the Costo-transverse. 

1. The Costo-vertebral articulation presents an anterior ligament, 
an inter-articular ligament, and two synovial membranes. The 
Anterior or Radiating Ligament, (Lig. Capituli Costarum,) is fixed, 
as its name expresses, in front of the joint. It arises from the 
margin of the head of the rib by the whole breadth of the latter, 
and diverging towards the spine, is fixed, by its superior fibres, 
into the vertebra above ; by its inferior fibres, into the vertebra 
below; and, by its middle fibres, into the inter- vertebral substance. 
It is a thin, flat, fibrous membrane, leaving intervals in it for the 
passage of blood vessels, and may, indeed, be considered as a cap- 
sule to the articulation, and is frequently described as such. The 
inter-articular ligament passes from the ridge on the head of the 
rib, to a corresponding line of the inter-vertebral substance. It is 
short and strong, and divides the articulation of the head of the rib 
into two cavities, which have no communication. It is in conse- 
quence of the latter, that there are two synovial membranes to the 
head of every rib which has a double articular face; but the ribs 

* Anat. Atlas, Figs. 103, 106. 



310 



SKELETON. 



which are articulated with a single vertebra, as the first, the eleventh, 
and twelfth, have not the inter-articular ligament, and, therefore, 
only one synovial membrane. 

The synovial membranes are not very apparent, neither is the 
fluid abundant ; the cavity is occasionally very small from the en- 
croachment of the inter-articular ligament. Anchylosis occasion- 
ally takes place here, but is more rare than in the anterior articula- 
tions of the thorax. 

2. The Costo-transverse articulation has, in addition to the joint 
formed between the tubercle of the rib and the end of the transverse 
process,, several ligamentous fasciculi which pass in varied directions. 

The synovial membrane is much more distinct than in the preceding 
articulation, and contains more synovia. The joint is more loose 5 
arid is never anchylosed, except by disease. There are a few fibres 
around it having the semblance of a capsule. 

The Internal Transverse Ligament (Ligamentum Transversarium 
Internum, or Costo-Transversarium Infeiius,) arises from the inferior 
margin of the transverse process, between its root and external ex- 
tremity, and proceeding downwards and inwards, is inserted into 
the upper margin of the neck of the rib below. In many of the ribs 
there is a plane of ligamentous fibres parallel with this ligament, but 
just behind, and arising from a more posterior situation of the trans- 
verse process to go to the neck of the rib, somewhat more towards 
the tubercle of the latter. It is designated by some writers as the 
posterior transverse ligament, but the distinction between it and the 
lig. trans, internum is so slight that it scarcely seems necessary to 
consider them apart. The Internal Transverse Ligament is much 
more conspicuous in the middle eight ribs, and in extremely emaci- 
ated subjects ; in others, it is obscured by cellular adipose matter 
around the heads of the ribs. 

The External Transverse Ligament (Ligamentum Transversarium 
Externum, or Costo-Transversarium Posterius) is a well-marked 
quadrangular plane of ligamentous fibres, placed on the posterior 
surface of the costo-transverse articulation. It arises from the ex- 
tremity of the transverse process, and going outwardly, is inserted 
into the proximate rib, just beyond its articular tubercle. 

The Middle Costo-Transverse Ligament (Ligamentum Cervicum 
Costarum, or Costo-Transversarium Medium) is extended between 
and concealed by the neck of the rib and the contiguous transverse 



ARTICULATIONS OF THE THORAX. 311 

process, and cannot be seen well without separating them, or by- 
sawing through their length. It is a collection of short fibres, some- 
what irregular, resembling condensed cellular substance, and slightly 
red. 

These posterior articulations all require a patient dissection, as 
they are surrounded by small parcels of adipose matter, have the 
intercostal nerves and blood vessels in contact with them before, 
and the muscles of the spine behind. The ligaments between the 
transverse processes and the ribs are, of course, not found in the 
eleventh and twelfth, from the bones not touching there. 

Besides what has been described, an aponeurosis or ligamentous 
membrane is extended from the transverse process of the first and 
second lumbar vertebra?, to the inferior margin of the last rib. A 
ligamentous membrane is also found near the spine, extended be- 
tween the contiguous margins of the last two ribs. 

Anterior Articulations of the Ribs* 

The surface of each pit in the side of the sternum is covered by 
a thin cartilaginous plate, to receive the corresponding cartilage of 
the rib, and the articulation presents an anterior and a posterior 
ligament, also a synovial capsule. 

The anterior ligament arises from the extremity of the cartilage, 
and, going over the front of the sternum, radiates very considerably 
in every direction. Some of its fibres are continuous with the cor- 
responding fibres of the opposite side ; others are lost in the perios- 
teum and in the tendinous origin of the great pectoral muscle ; others 
join the fibres of the ligament above, and of that below. The more 
superficial the fibres are, the longer they become ; but the more 
deeply seated pass only from the margin of the cartilage to the mar- 
gin of the cavity in the sternum. The thick ligamentous covering 
found on the front of the sternum, may be considered as only the 
continuation of these anterior ligaments. The fibres from the two 
lower articulations on the opposite sides, form, by their junction, a 
striking triangular ligamentous plane, just on the lower end in front 
of the second bone of the sternum. Besides which, there are seve- 
ral strong ligamentous fasciculi running in a great variety of direc- 
tions. 

* Anat. Atlas, Figs. 35, 113. 



312 



SKELETON. 



The posterior ligament has a similar arrangement with the ante- 
rior, in the radiation of its fibres into the contiguous ligaments, and 
in their origin from the costal cartilage. Altogether they form, on 
the posterior face of the sternum, a strong smooth covering, the 
fibres of which do not run in large fasciculi, but make a uniform 
polished membrane, and are closely interwoven with each other. 
Some of these fibres are longitudinal, and, of course, cannot be 
referred to the posterior ligaments, but are independent of them. 

The synovial membrane though its existence is admitted, is not 
in a very distinct state. It scarcely gives a polish to the articular 
surfaces, and has so little looseness in its reflection from the one to 
the other, as to indicate clearly that but an inconsiderable motion is 
admitted in these joints. The synovia is in very small quantity, not 
abundant enough for satisfactory examination, and its character is 
rather inferred than proved. The first cartilage is continuous with 
the sternum, and not separated from it by any joint, except in rare 
instances. The second cartilage has its joint with the sternum, 
separated into two, one above and the other below, by a ligamen- 
tous partition resembling that at the heads of the ribs. The lower 
articulations become, successively, more moveable than the upper. 

Besides the attachments mentioned as connecting the cartilages 
of the true ribs to the sternum, there is one superadded to the 
seventh cartilage, called the Costo-Xiphoid Ligament. It arises 
from the inferior margin of the seventh cartilage, near the sternum, 
and going obliquely downwards and inwards, is inserted into the 
anterior face of the xiphoid cartilage, and has its upper fibres run- 
ning into the corresponding fibres of its fellow. It is, of course, 
placed behind the rectus abdominis muscle, and fills up, in some 
measure the angle between the seventh cartilage and the third piece 
of the sternum. 

At the surfaces where the sixth and seventh cartilages come into 
contact by their edges, also the seventh and eighth, a synovial mem- 
brane exists. A similar articulation is sometimes found between 
the fifth and sixth, and the eighth and ninth cartilages, but not uni- 
formly. These synovial membranes are covered by a strong fibrous 
capsule. 

It has been already stated that the anterior extremity of the carti- 
lage of each of the first three false ribs, is united by ligamentous fibres 



ARTICULATIONS OF THE UPPER EXTREMITIES, 313 

to the cartilage above. These ligaments are strong and extensive, 
and give great solidity to the common margin of the cartilages. 
The last two cartilages being much smaller than the others, no liga- 
ments pass from them ; but they, with their ribs, are held in their 
position by the intercostal and the abdominal muscles. 

The cartilages adhere very closely to their respective ribs, which 
receive them into the oblong fossa, at their anterior extremities. 
The periosteum of the rib is continuous with the perichondrium of 
the cartilage, and the membrane, which is in fact, one and the same, ' 
adheres very closely to the margins of the articulation ; it is also re- 
enforced by some ligamentous fibres beneath it. No motion what' 
ever is admitted at this articulation. 



CHAPTER VIII. 
Of the Articulations of the Upper Extremities. 

Of the Articulations of the Shoulder* 

These articulations consist in the junction of the clavicle to the 
upper part of the sternum, and to the cartilage of the first rib ; of the 
scapula to the clavicle, and of the os humeri to the scapula. 

Of the Sterno* Clavicular Articulation. 

The uneven triangular face of the internal end of the clavicle, 
and the concavity of the sternum, at its upper corner, form the 
surfaces which enter into this articulation. The first is much more 
extensive than the articular surface of the sternum, projects on every 
side beyond its margins, and is very prominent in case of extreme 
emaciation. The two surfaces are covered by cartilage, of which 
that on the clavicle is the thickest, and serves to fill up its inequali 
ties ; while the one on the sternum is thin and smooth. 

* Anat. Atlas, Figs. 113, 114. 
Vol. I.— 27 



314 



SKELETON. 



The joint is invested \>y a thick fibrous capsule, the anterior por- 
tion of which presents a strong fasciculus of fibres somewhat sepa- 
rated by small interstices. This portion, called by some the radiated 
ligament, arises from the anterior extremity of the clavicle, and, 
going downwards and inwards, is inserted into the margin of the 
articular cavity of the sternum. It is placed just behind the origin 
of the sterno-cleido mastoid muscle. The capsular ligament is also 
strengthened on its posterior surface by additional fibres, not so 
* distinct as the preceding, but obtaining the name of the posterior 
ligament. 

Of the Inter- Clavicular Ligament, (Lig. Inter- Clavicular e.) — 
Closely connected with the capsule of the preceding joint, this liga- 
ment is placed on the superior end of the sternum, and extends 
from the internal end of one clavicle to that of the other. It is flat 
before and behind, thin and narrow, is blended with the contiguous 
ligamentous structure of the sternum, and might, with propriety, 
be considered only an appendage to the capsular ligaments, or a 
process sent between them. In front it corresponds with the integu- 
ments, and behind with the sterno-hyoid muscles. 

Of the Inter -Articular Cartilage. — When the capsule of the joint 
is cut open, this is brought into view. It separates the bones com- 
pletely from each other by its extent, and supplies by its shape 
the want of correspondence in their articular faces. It is thicker 
above than below; its centre is thin, and sometimes perforated. 
Its margins adhere closely to the capsular ligament; it is also fixed 
by adhesion to the upper posterior margin of the surface of the 
clavicle, and below to the union of the sternum with the cartilage 
of the first rib; in consequence of which it has but little motion, 
and in luxations must be lacerated. Its structure is fibro-cartila- 
ginous. 

Of the Synovial Membranes. — There are two of these, one on 
each side of the inter-articular cartilage; in consequence of which, 
a double cavity exists in this articulation, excepting the cases 
where the cartilage is perforated. These membranes contain but 
little synovia: they adhere closely to the adjoining surfaces, and 
cannot be made very distinct, except in points where there are 



ARTICULATIONS OF THE UPPER EXTREMITIES. 315 

small interstices in the capsule, when, by pressing the bones strongly 
together, they protrude in little vesicles. 

Of the Costo- Clavicular Articulation. — It consists in a short 
fasciculus of ligamentous fibres, frequently called the Rhomboid 
Ligament, which, arising from the upper surface of the cartilage of 
the first rib, ascends obliquely outwards, and is implanted into the 
roughness on the inferior face of the clavicle, near its sternal end. 
Its fibres are parallel, all oblique, and longer at its external than at 
its internal margin. It corresponds in front with the origin of the 
subclavius muscle, and behind with the subclavian vein. It has 
for its object the strengthening of the junction of the clavicle with 
the sternum. 



Of the Scapulo- Clavicular Articulations. 

These exist at three places; the first by a junction between the 
acromion scapulas and the external end of the' clavicle; and the last 
two by ligaments sent from the coracoid process to the under sur- 
face of the clavicle. 

The Acromio- Clavicular Articulation presents, on each bone, a 
small oblong face, covered with cartilage. The fibrous capsule 
which invests it is very strong and thick, so as to give the appear- 
ance of a much greater extent to the articular faces of the bones 
than really exists. This capsule is strengthened by additional fibres 
on its upper surface, passing from one bone to the other, and some- 
times called the superior ligament: they are parallel to each other, 
and somewhat blended with the tendinous fibres of the deltoid and 
trapezius muscles. The capsule is also strengthened on its lower 
face, by additional fibres, constituting the inferior ligament ; they 
are not so abundant as the superior, and pass from the margin of 
one 1 bone to that of the other, after the same manner. A synovial 
membrane is reflected over these articular surfaces, and contains 
but a very small quantity of fluid. In some instances, an inter- 
articular fibro -cartilage is found in this joint; as in the sterno-cla- 
vicular; in such case there is a double synovial membrane. 

Of the Coraco- Clavicular Ligament. — This ligament is double, 



316 



SKELETON. 



one part being called the Conoid {Lig. Conoides) and the other, 
the Trapezoid (Lig. Trapezoides.) It arises from the roughness at 
the root of the coracoid process, and is attached to the under surface 
of the clavicle. The conoidal portion, having its base upwards, 
is inserted into the tubercle, near the external end of the clavicle. 
Its fibres are compact, strong, and diverging. The trapezoid is 
placed at the acromial side of the other. It is quadri-lateral, longer, 
broader and thinner than the other, having its fibres separated by 
small interstices; and arising also from the root of the coracoid pro- 
cess, it is inserted into an oblique line leading from the tubercle of 
the clavicle to its acromial end. The union of these two portions 
behind forms a projecting angle; in front there is a depression be- 
tween them filled with fat and cellular substance, also a bursa 
mucosa. These ligaments are bounded in front by the subclavius, 
and behind by the trapezius muscle. 

The Bifid Ligament (Ligamentum Bicorne) is placed in front of 
the subclavius muscle. It arises from the root of the coracoid pro- 
cess, at the sternal side of the conoid ligament: and proceeding with 
but little elevation, inwards and upwards, increases in breadth and 
bifurcates. The superior horn is inserted along the under margin 
of the clavicle to near the rhomboid or costo-clavicular ligament ; 
but the lower one goes to the end of the first rib, under the tendon 
of the subclavius muscle. This ligament is a sort of fascia placed 
over the subclavius muscle to bind and strengthen it.* Some of 
the fibres of the superior horn occasionally proceed farther, and 
leaving the clavicle, go with the rhomboid ligament into the carti- 
lage of the first rib. f 

Of the Scapular Ligaments,. 

The Coracoid Ligament (Lig. Coracoideum) stretches across the 
notch on the superior costa of the scapula, and converts it into a 
foramen. It runs from the posterior margin of the notch to the base 
of the coracoid process, and has some of its fibres blending with the 
conoid ligament. It consists of a small fasciculus of fibres, and is 

* This ligament is called the clavicular fascia by M. M. Velpeau and Blandin, 
in their treatises on surgical anatomy. 
t Caldani, Plate XLI. 



ARTICULATIONS OF THE UPPER EXTREMITIES. 317 

of very little consequence, excepting in its relation to the superior 
scapular vessels and nerves. 

The Triangular Ligament (Lig. Coraco-Acromialis) of the Scapula, 
as its name implies, extends from the coracoid to the acromion pro- 
cess above the shoulder joint. It arises from nearly the whole 
superior margin of the coracoid process, in two divisions, separated 
partially by cellular tissue. Its fibres converge in their progress, by 
which it becomes thicker, and is inserted into the point of the acro- 
mion process, just beneath its junction with the clavicle. This 
ligament is covered by the deltoid muscle and the clavicle, and has 
the supra-spinatus beneath it. Its anterior margin is continuous 
with a condensed cellular membrane beneath the deltoid. 



Of the Scapulo- Humeral Articulation. 

The glenoid cavity of the scapula, and the head of the os humeri 
form this joint. As usual, each articular surface is covered with 
cartilage, of which that on the os humeri is thicker in the middle 
than near its circumference, while the reverse occurs on the scapula. 
From the shallowness of the glenoid cavity and the much greater 
size of the head of the os humeri, but very few points of their 
opposed surfaces can come into*contact at the same moment, though 
they may all do so in succession : hence a considerable portion of the 
head of the os humeri, is always against the capsule of the joint. 
The remaining parts of this articulation are the capsular ligament, 
the synovial membrane, and the glenoid ligament. 

The Capsular ligament invests completely this joint, though it is 
thinner in some places than at others. It arises from the margin of 
the glenoid cavity, and is inserted into the neck of the os humeri, 
including a larger space of the neck below, than it does above. The 
tendons of the muscles which arise from the external and internal 
surface of the scapula, to be inserted into the tuberosities of the os 
humeri, as they approach their points of insertion, adhere very closely 
to the capsular ligament, and are, indeed, more or less blended with 
it. Bichat considers that the tendon of the sub-scapularis muscle 
supplies the place of the capsular ligament entirely at its lower part. 
This ligament is formed by fibres which are very much intermixed 

27* 



318 



SKELETON. 



with one another, and have a greater degree of thickness above than 
below, or indeed, at any other point. The former is due to a thick 
fasciculus, the Coraco-Humeral Ligament, also called by some, Liga- 
mentum Ascititium, which takes its origin from the posterior and ex- 
ternal margin of the coracoid process, and proceedingbeneath the trian- 
gular ligament to the upper part of the os humeri, joins the capsular 
ligament, and adheres very firmly to it. This ligament keeps the 
head of the os humeri on its proper level in regard to the glenoid 
cavity ; but the moment it is cut, the length of the capsular liga- 
ment permits the head of the os humeri to fall about an inch, and, 
indeed, to suffer a partial dislocation. The strength of the joint, 
however, depends essentially upon the muscles which surround it, 
as the deltoid, supra-spinatus, infra-spinatus, teres minor, sub-sca- 
pularis, long head of the triceps, and some others, which are farther 
removed from it. 

The Synovial membrane is a perfect sac, w T hich covers the glenoid 
cavity, the internal face of the capsular ligament, and the neck and 
head of the os humeri. On the lower part of the neck it is reflected 
over some small fatty masses, commonly called glands. Just be- 
neath the root of the coracoid process, from there being a deficiency 
of the capsular ligament, the synovial membrane covers the articular 
side of the tendon of the sub-scapularis, and is reflected for ten or 
twelve lines, between it and the scapula, forming a sort of pouch, 
resembling a bursa mucosa. 

The tendon of the biceps muscle runs through this articulation 
from the superior end of the glenoid cavity. The cavity itself is 
deepened by a fibrous margin all around called the glenoid ligament; 
a considerable part of whose fibres maybe traced from the tendon of 
the biceps by its bifurcating. The tendon is bound down in the bi- 
cipital groove by fibres passing from one to the other of the bony 
margins, and which may be considered a continuation of the cap- 
sular ligament. As the tendon is about emerging from the groove 
at the lower margin of the tuberosities, the synovial membrane 
which lines the groove thus far, is reflected from it, to the surface of 
the tendon, and continues to cover and enclose it up to the origin 
at the glenoid cavity. It is thus evident that though the tendon 
passes through the joint, the cavity of the synovial membrane is 
t entire. 



ARTICULATIONS OF THE UPPER EXTREMITIES. 319 

Of the Elbow Joint* 

This articulation is formed by the lower end of the os humeri and 
the upper end of the ulna and of the radius. The articular faces 
which were described in the account of these bones are covered, as 
usual, with cartilage, the particular arrangement of which will be 
presently pointed out. A strong capsular ligament, an annular or 
coronary ligament, and a synovial membrane, hold these several 
bones together. 

The Capsular Ligament invests completely the articular extremi- 
ties of these bones, and conceals them from view. It is attached to 
the sides of the os humeri at the lower part of its condyles near the 
articular surface, but in front it arises some distance from the arti- 
cular face at the upper margins of the sigmoid cavities, for the head 
of the radius and for the coronoid process of the ulna : behind, it 
arises in like manner from the upper margin of the cavity for re- 
ceiving the olecranon process ; so that the depressions, both before 
and behind, are included within the circumference of the articulation. 
The lower part of the capsular ligament is inserted into the margin 
of the articular surface of the ulna, all around, including, also, the 
whole of the head of the radius, and the upper part of its neck. 

This capsule is strengthened very much at particular points, and 
as the joint is hinge-like, the strengthening is more abundant at its 
sides, constituting lateral ligaments. 

The External Lateral, or the Brachio Radial ligament, (Lig. Cubi- 
ti Externum,) is connected above to the lower part of the external 
condyle, and is fixed below into the annular ligament which sur- 
rounds the neck of the radius. It is very much confounded with 
the tendinous mass common to the muscles at this part of the arm, 
more particularly that of the supinator radii brevis. It is a round 
fasciculus of parallel and condensed fibres, spreading somewhat 
below into the annular or orbicular ligament. The Internal Lateral 
or the Brachio Ulnar Ligament, (Lig. Cubiti Internum) arises from 
the lower part of the internal condyle, and spreading out so as to 
assume a triangular shape, divides into two portions, one of which 
is inserted into the internal margin of the coronoid process of the 

* Anat. Atlas, Figs. 115, 11C. 



320 



SKELETON. 



ulna, and the other into the internal margin of the olecranon process. 
It also is much blended with the tendons of the muscles which lie 
over it. Intermediately to the lateral ligaments, both before and 
behind, the fibrous structure of the capsular ligament is very distinct, 
but thin, in order to accommodate the motions of the joint ; many 
of the fibres are insulated, and have interstices between them filled 
with fat. Some of these fibres are oblique, and others straight: 
they are called, in common, Accessory ligaments. 

The Coronary Ligament of the Radius (Lig. Radii Orbiculare) 
is brought more distinctly into view by cutting open the joint. It 
is then seen to arise from the anterior margin of the lesser sigmoid 
cavity of the ulna, and surrounding two-thirds of the neck of the 
radius, to be inserted into the posterior margin of the same cavity. 
It is a strong, flat, narrow fasciculus, the fibres of which go in a 
circular direction. Its superior margin is blended with the exter- 
nal lateral ligament: its inferior margin is loose, being connected 
with the lower part of the neck of the radius only by a reflection of 
the synovial membrane, with the exception that a few fibres pass 
from it behind, to the contiguous part of the ulna. Its density is 
very considerable, sometimes almost cartilaginous. 

The Synovial Membrane lines the whole internal face of the 
capsular ligament, from which it is separated behind by a large 
mass of fat in the olecranon depression of the os humeri, and in 
front by another mass in the coronoid depression. A small circular 
ridge of fat also projects into the joint around the head of the radius, 
and there is another at the internal margin of the olecranon. The 
object of these masses seems to be to fill up the partial vacancies which 
exist between the articular faces of the bones, and they are all so 
directed by their attachment to the capsular ligament, as to be pre- 
served from being pinched. The synovial membrane is also re- 
flected from the capsular ligament to the articular faces of the bones, 
so as to line the several depressions on the os humeri, and to include 
the neck of the radius. 

The head of the radius is completely invested with cartilage. 
The greater sigmoid cavity of the ulna has its articular cartilage 
separated transversely into two portions, by a small layer of fat 
traversing its bottom. The cartilage elsewhere is uniformly spread 
over the articular surfaces of the bones. 



ARTICULATIONS OF THE UPPER EXTREMITIES. 321 

Of the Interosseal Ligament, (Mernbrana Intei-ossea.) — It fills up 
the space between the two bones of the fore arm almost entirely, by 
commencing just below the tubercle of the radius and ending near 
the wrist. It consists in oblique parallel fibres, which pass from 
the ulnar edge of the radius downwards to the radial edge of the 
ulna. It is thin, but extremely strong, being covered in front by 
the flexor muscles; and behind by the extensors; and, as Mr. 
Boyer observes, seems to be intended rather to afford origin to 
muscles than to unite the bones. Its superior part is thinner above, 
and a large opening exists there for the passing of the interosseal 
vessels to the back of the fore arm. Its inferior part is thick, where 
openings also exist, but small, for the passing of vessels. There 
are some other smaller perforations in this ligament, but of less note 
than the preceding, also for vessels. On its posterior face there are 
one or two bands, the fibres of which decussate the other fibres. 

Besides the interosseal ligament, there is one called Round (Teres,) 
situated obliquely between the two bones at the upper part of the 
interval which separates them. It arises from the base of the co- 
ronoid process, just below the insertion of the brachialis internus; 
and descending obliquely outwards, is inserted into the radius 
below its tubercle. Its object is to bind the bones together, at a 
point which is weakened by the deficiency of the interosseal liga- 
ment. This deficiency is, in fact, much larger than the simple 
passing of the vessels requires; for it is also large enough to allow 
the tubercle of the radius to rotate freely, a motion which would 
have been checked by the presence of the ligament. The round 
ligament acts also as a check upon the undue supination of the 
hand. It is frequently defective. 



Of the Articulations of the Wrist* 

Several articular cavities present themselves at this point. One 
is between the lower part of the ulna and the radius, another be- 
tween the carpal bones and those of the fore arm, and a third be- 
tween the two rows of carpal bones. One general capsule invests 
these parts. 

1. The Lower Radio Ulnar Articulation — is surrounded by a 
* Anat. Atlas, Figs. 117, 118. 



322 



SKELETON. 



section of the fibres belonging to the general capsular ligament of 
the wrist: their attachment, however, is so loose, that they allow 
the bones to rotate freely upon each other, besides which they are 
not so abundant as in other places. When this joint is cut open, 
it will be seen that the head of the ulna is covered with cartilage, 
and tiiat the cartilage which covers the carpal articular face of the 
radius, projects between (he ulna and the os cuneiforme. It covers 
also the sigmoid cavity of the radius; so that a cavity for receiving 
the convex head of the ulna is formed by the cartikge of the radius. 
The margins of the above projecting point of the radial cartilage 
are fibrous, which has induced the French anatomists to speak of 
it under the name of triangular ligament. It is, in fact, an inter- 
articular fibro-cartilage, and is said to be occasionally detached from 
the radius, but I have not seen it in that state: its centre not unfre- 
quently is perforated, so that a communication exists between this 
joint and the next of the wrist. Its margins adhere very closely to 
the capsular ligament, and its point is fixed into the depression 
which separates the styloid process of the. ulna from its head. The 
synovial membrane which lines this cavity is unusually loose, both 
before and behind, in consequence of the great motion of the bones: 
it is also very loose above. This joint is sometimes called the 
Sacciform, from its looseness. 

2. Of the Radio-Carpal Articulation. — The radius above, and the 
scaphoides, lunare, and cuneiforme below, form the basis of this 
articulation. An oblong elliptical cavity, the ulnar extremity of 
which is made by the projection of the above cartilage of the radius, 
receives the convexity of the bones of the wrist. The scaphoides 
and the lunare come in contact with the radius, while the cuneiforme 
rests against the projecting cartilage. There is a slight elevation of 
the radial cartilage opposite to the interstice between the first two 
bones. The oblong elliptical cavity is filled by a corresponding 
head, on the part of the bones of the carpus just enumerated. Each 
of the latter bones, in a fresh state, is covered by its appropriate 
cartilage. The cartilages are connected, or rather continued into 
one another, by a narrow fibro-cartilaginous substance placed at the 
margin of the interstice between these bones. This substance sepa- 
rates the cavity of the radio-carpal articulation from that of the proper 
carpal articulation. 



ARTICULATIONS OF THE UPPER EXTREMITIES. 323 

The Capsular Ligament arises, before and behind, around the 
margin of the articular face of the bones of the fore arm, from the 
styloid process of the radius to that of the ulna, adhering very closely 
to the margins of the fibro-cartilage insinuated between the ulna and 
the cuneiforme. It is inserted below, into the circumference of the 
head formed by the scaphoides, lunare, and cuneiforme, though 
many of its fibres may be traced to the bones of the second row. 
It is a loose and thin membrane, the fibrous fasciculi of which leave 
interstices at several points between them, through which the syno- 
vial membrane may be seen. The capsular ligament is strengthened 
at particular places, by additional fasciculi of fibres having appro- 
priate names. For example, the Internal lateral ligament arises 
from the styloid process of the ulna, and is inserted into the cunei- 
forme, some of its fibres being extended to the anterior annular 
ligament, and to the pisiforme. The External lateral ligament arises 
from the styloid process of the radius, and is inserted into the radial 
end of the scaphoides : some of its fibres being continued on to the 
trapezium, and to the anterior annular ligament. The anterior liga- 
ment arises from the vicinity of the styloid process of the radius, 
and passing obliquely downwards and inwards, is inserted into the 
anterior face of the scaphoides, lunare, and cuneiforme. Its fasci- 
culi are not very evident or well marked. The posterior ligament 
is not so broad as the last, and is more distinct. It also arises from 
the radius, by and near its styloid process, and descending obliquely 
inwards, is inserted into the lunare and cuneiforme. The last two 
ligaments have no connexion with the ulna, the rotation of the fore 
arm is, therefore, unimpeded by them.* 

The synovial membrane of the radio-carpal articulation is dis- 
played on the articular faces of the bones and their intermediate 
fibro-cartilage, and lines the internal face of the capsular ligament. 
When the joint is pressed upon, this membrane is protruded, in the 
form of little vesicles, in the interstices between the fasciculi of the 
capsular ligament. A fold of it containing a small quantity of 
adipose matter is observed on the back of the cavity of the joint, 
passing from the junction of the scaphoides and lunare to the cor- 



* The ligamentous character of these several fasciculi is best seen on the 
surface next the cavity of the joint. 



324 



SKELETON. 



responding point of the radius ; it is the ligamentum mucosura of 
some writers. 

3. Of the Articulation between the two rows of the Carpal Bones. 
— The scaphoides, lunare, and cuneiforme of the first row, and all 
the bones of the second row, are the foundation of this joint, the sur- 
faces of which have been described already. These surfaces are 
covered with cartilage, each bone having its appropriate cartilage, 
which is continued on its side where the bonetouches the adjacent 
one. The joint is furnished with a capsular ligament and a syn- 
ovial membrane. 

The Capsular Ligament surrounds the articulation, passing on 
every side from the upper to the lower row, and adhering strongly 
to the bones. It is in a great degree a continuation of the capsule 
of the radio-carpal joint, and has, at the same points, an increase of 
thickness, called after the same names. The internal lateral liga- 
ment is attached by one end to the cuneiforme, and by the other to 
the side of the unciforme. The external lateral ligament arises from 
the extremity of the scaphoides, and is inserted into the side of the 
trapezium. The posterior and anterior ligaments have the course of 
their fibres more distinctly seen on the side of the synovial membrane. 
The first consists in many fibres arising from the bones of the first 
row and going to the second row ; its fibres are shorter and more 
compact. The anterior arises and is inserted after the same way, 
some of them terminating in the anterior ligaments of the hand. 

The Synovial Membrane is not only displayed on the opposite 
surfaces of the two carpal rows, but also is reflected upon the lateral 
faces of the bones belonging to each row. It, therefore, sends pro- 
cesses, two of which are found, above ; one between the scaphoides 
and the lunare, and the other between the lunare and cuneiforme. 
These processes are arrested at their upper extremities by the fibro- 
cartilaginous matter between the bones, which was spoken of in the 
radio-carpal articulation. It also sends three processes downwards, 
one between the trapezium and the trapezoides, another between 
the latter and the magnum, and the third between the magnum and 
the unciforme. Of those latter processes, two or three, communi- 
cate with or, are continuous with the synovial membrane, between 



ARTICULATIONS OF THE UPPER EXTREMITIES. 325 

the carpal and the metacarpal bones of the fingers.* The connexions 
and reflections of this membrane are of the greatest importance, as 
they form a communication from the top of the wrist to the base of 
the metacarpal bones ; not only covering the articular surfaces, but 
being prolonged in some instances beyond them, as on the back of 
the os magnum, where it answers as a periosteum. 

In addition to the articulation just described, between the two 
rows of carpal bones, the individual bones of each row have parti- 
cular fastenings of ligamentous fibres, which run transversely from 
the margin of one bone to the margin of the next. These fibres, 
from their position, are called dorsal and palmar ligaments. The 
upper row has one dorsal ligament between the scaphoid and lunar, 
and another between the latter and the cuneiforme — it has in the 
same way two palmar ligaments on its front surface. The lower 
row has, after the same plan, three dorsal and three palmar ligaments 
between its bones. These several ligaments are best seen on the 
side of the synovial membrane, as externally their fibres are very 
much mixed with those of the capsular ligament. It is obvious that 
they are highly useful in preventing the bones from sliding laterally 
on each other, except to a small extent. 

The Pisiform Bone has an articulation with the cuneiforme com- 
pletely distinct from any other. The articular faces of this joint are 
covered with cartilage and invested by a synovial membrane and a 
capsular ligament, which allow, from their looseness, considerable 
motion. The capsule, though generally thin, is strengthened by acces- 
sory fibres, which are well marked below. These fibres arising from 
the inferior extremity of the pisiform, some of them are attached to 
the extremity of the unciform process of the os unciforme, and others 
to the base of the fifth metacarpal bone. The insertion of the tendon 
of the flexor carpi ulnaris answers as a ligament to this bone above, 
and as there is a very strong fasciculus of ligament, passing from 
the pisiforme to the end of the unciform process, by that means the 
action of the flexor ulnaris is conveyed to it, and the pisiform 
thereby is prevented from being pulled out of its place. The Pisi- 
form has but little motion from above downwards, and a good 
deal laterally. 

* Bichat, Anat. Descr. 
Vol. I.— 28 






326 



SKELETON. 



Of the Carpo -Metacarpal Articulations. 

The bony articular surfaces, here, as well as all the others of the 
hand, have been sufficiently described and are in the recent state 
covered with cartilage. It will therefore be unnecessary to renew 
the observations on these subjects. 

The first of these articulations, or that of the metacarpal bone of 
the thumb, with the trapezium, is much more moveable than any of 
the others, and presents some peculiarities. It is entirely distinct, 
from the others, slightly removed from the next, and is surrounded 
by a capsule which is attached by its ends to the articular margins 
of the bones. This capsule is strengthened by additional fibres, 
which are particularly strong and abundant, posteriorly and exter- 
nally. The synovial membrane is displayed, as usual, on the inter- 
nal face of the capsule, and over the articular faces. 

The other four metacarpal bones are articulated as follows: The 
second one is joined to the trapezoides, trapezium, and magnum — 
the third unites to the magnum alone — the fourth to the unciform, 
with a small portion of the magnum — and the fifth to the unciform. 
The ligaments are placed before and behind, and may also be termed 
dorsal and palmar. 

The dorsal ligaments descend from the carpal to the metacarpal 
bones. The second metacarpal bone receives two ligaments, one 
from the trapezium, and another from the trapezoides — the third 
receives one from the magnum — the fourth receives two, one from 
the magnum, and the other from the unciform — the fifth receives 
one from the unciform. Transverse fibres pass between these dorsal 
ligaments to connect the bases of the metacarpal bones. 

The palmar ligaments are arranged on a plan corresponding with 
that of the dorsal; but, from the length of their superficial fibres, 
are not so distinct from each other. Transverse fibres pass also 
between the metacarpal bones of the fingers at their base, and form 
interosseous ligaments which keep them together. 

The articulations thus formed and held together, are covered by 
two synovial membranes, being processes from that between the 
two rows of carpal bones. One of these processes, sent down 
between the trapezoides and the magnum, displays itself over the 
inferior surface of these bones and the head of the metacarpal bone 



ARTICULATIONS OF THE UPPER EXTREMITIES. 327 

of the fore and of the middle finger. The second process which is 
sent down between the magnum and the unciforme, is reflected 
over the last two carpo-metacarpal articulations. These processes 
have a septum between them, at the ulnar side of the base of the 
third metacarpal bone, and do not communicate with each other, 
except through the proper carpal articulation. The specification of 
this arrangement is overlooked by anatomists generally. 

The Inferior Palmar Ligaments are three in number, and are 
between the lower ends of the metacarpal bones of the fingers, 
each one consists in a transverse fasciculus, placed between the 
flexor tendons and the interosseous muscles, and on a level with 
the anterior part of the first joint of the fingers. Their more super- 
ficial fibres may be traced across the bones, and are somewhat 
blended with the capsular ligaments; the more deep-seated are 
short, and pass from one bone to the other. 



Of the Metacarpo-Phalangial Articulations. 

These are formed by the lower ends of the metacarpal bones, and 
the upper ends of the first phalanges. Each one presents an anterior 
ligament, two lateral ones, and a synovial membrane. 

The anterior Ligament* is a flat fibrous semicircle, on the front 
of the articulation, and of considerable thickness. It goes trans- 
versely, and has its two extremities attached to the ridge on either 
side of the articular margin of the metacarpal bone. Its inferior 
margin descends a little, and comes in contact with the synovial 
membrane. In front, many of its fibres are obtained from the fibro- 
cartilaginous sheath of the flexor tendons, so that it may be consi- 
dered as made by two planes — the palmar one facing towards the 
tendons, and forming the trochlea, in which they play, and the other 
being next to the joint, and continued to the lateral ligaments. 
The thickness of the anterior ligament, besides communicating great 
strength to the joint is useful in removing the tendons from the line 
of motion of the phalanges, and thereby giving increased power 
and delicacy of motion to the muscles. Bichat considers himself 
to have first indicated particularly this structure, which he thought 
was intended to protect the articulation from the impression of the 

* Bichat, loc. cit. 



°^° SKELETON. 

tendon: to which may be added, in the firm grasping of bodies, and 
to make the movements of the joint more delicate. On the sides 
of this ligament belonging to the thumb, and in its thickness, are 
developed the sesamoid bones. 

The Lateral Ligaments are situated one on each side. They 
arise at the pits or the sides of the metacarpal bone behind the 
former, and in connexion with it, and, descending obliquely for- 
wards, are fixed into the sides of the upper end of the first phalanx. 
They are round, distinct, and strong, and are formed from numerous 
parallel fibres. 

The Synovial Membrane lines this articulation, being displayed 
over its lateral and anterior ligaments, and on the articular faces of 
the bones. It is reflected on the metacarpal bone, some little dis- 
tance from the margin of its cartilage in front, whereby the cavity is 
enlarged, and the flexion of the fingers is favoured. It is in contact, 
behind with the tendon of the extensor muscle, which there supplies 
the place of ligament. 



Of the Phalangial Articulations. 

There are two of these to each finger, and one only to the thumb. 
They are provided with an anterior ligament, a lateral ligament on 
each side, and a synovial membrane. 

The anterior Ligament corresponds so exactly with what has been 
said in the preceding article on the same structure, that, with the 
exception of its being smaller, the description already given will 
suffice. It seems to answer in every respect, the same objects. 

The Lateral Ligaments, also, arising from the sides of the pha- 
lanx above, run downwards and somewhat forwards to be inserted 
into the upper part of the sides and the base of the phalanx below. 

The Synovial Membrane has reflections corresponding with those 
of the preceding articulations, with the addition that it covers 
more of the anterior inferior face of the first and second phalanges. 
Thus, by cutting through the anterior ligament, longitudinally, and 



ARTICULATIONS OF THE LOWER EXTREMITIES. 329 

turning it aside, it will be seen that the cavity of the second and 
third joints of the finger is, by this reflection of the synovial mem- 
brane, extended upwards between the phalanx and the flexor ten- 
dons nearly one-third of the whole length of the phalanx,* a cir- 
cumstance worth attending to in the accidents of the part. The 
synovial membrane from the deficiency of capsular ligament behind, 
is also in contact there with the extensor tendon, as the latter sup- 
plies the place of ligament. Hence all the joints of the fingers are 
very near the surface upon their posterior semi-circumference and 
easily laid open by accident. 



CHAPTER IX. 
Of the Articulations of the Lower Extremities. 

Of the Ilio- Femoral, or Hip Articulation. -\ 

The basis of this articulation is laid by the head of the os femo- 
ris being received into the acetabulum. Both surfaces are covered 
by thick cartilage : in the former it is interrupted, however, by the 
depression near the centre, and becomes very thin near the margin ; 
and in the latter, the cartilage is deficient in the whole extent of the 
rough surface at its lower part. A cotyloid ligament, a fibrous 
capsule, the round or inter-articular ligament, and a synovial mem- 
brane, are moreover, concerned in this joint. 

The Cotyloid Ligament (Lig. Cotyloideum) is a fibrous prismatic 
ring which tips the margin of the acetabulum, and thereby increases 
its depth ; it can only be seen by cutting open the capsule. Its 
thickness is unequal, being considerable on the anterior third of the 
circumference of the acetabulum, where it assists in converting the 
notch into a foramen, but not so much so elsewhere. Just below 
the anterior inferior spinous process the acetabular head of the rectus 
femoris sends some tendinous fibres to it. Its base is broader than 
its margin, and is marked off from the articular cartilage by a cre- 
vice, or narrow groove, between them. Its acetabular side is 

* Bichat, loc. cit. f Anat. Atlas, Fig. 119. 

28* 



330 



SKELETON. 



covered by the synovial membrane : the other side has the capsular 
ligament adhering to it, and the third side adheres to the bone. 
Where it subtends the notch of the acetabulum, the cotyloid liga- 
ment is re-enforced by additional ligamentous fibres, placed beneath 
it, and going from the upper to the lower end of the notch : these 
fibres consist of two planes, one internal and the other external, 
partly crossing each other, and adhering closely to the cotyloid 
ligament. 

The Inter-Articular, or Round Ligament, (Lig. Teres,) is a true 
ligamentous band, which is attached at the one end to the pit on 
the head of the os femoris, and afterwards by a slight dissection, 
is easily separated into two fasciculi. Of these, the lower one may 
be traced to the inferior end of the cotyloid notch, where, winding 
around the prominence of bone, it begins to adhere to the ischium, 
and continues to do so from that point along the ant.erior face of the 
ischium, just below the acetabulum, to a point between the latter 
and the upper anterior part of the tuber. The other portion is 
directed towards the superior end of the notch, and is attached there 
by two extremities, one near the margin of the acetabulum, and the 
other three or four lines from it within.* The fibres of the round 
ligament are somewhat intermixed also with those of the cotyloid 
ligament subtending the notch. 

The Capsular Ligament (Capsula Fibrosa) is the strongest in 
the body, and represents a conoidal sac, open at both extremities, 
by which it adheres to the bones. It is fixed by its base to the cir- 
cumference of the acetabulum, beyond the cotyloid ligament, and 
into this ligament itself, where the latter subtends the notch. It 
embraces that part of the head of the os femoris which projects 
above the margin of the acetabulum, and descends along the neck 
to its root. It is longer in front ; is fixed there to the oblique line 
which runs between the two trochanters, and, behind, into the root 
of the neck, a little in advance of the posterior oblique ridge, and in 
such a manner as to leave a small part, six or eight lines broad, of 
the neck of the os femoris bare below it. Above, it is fixed to 
the neck, just below the rough fossa in the trochanter major ; and 
on the under surface of the neck it adheres, just above the trochanter 
minor. It is strengthened in several places by processes from the 

* Antonius et Caldani, Tabula II, 



ARTICULATIONS OF THE LOWER EXTREMITIES. 331 

fascia lata femoris, which descend to it between the muscles sur- 
rounding the hip-joint.* Its thickness is considerable, but variable. 

In front, and above, it is remarkably strong, is two or three lines 
thick, where it is re-enforced by a large fasciculus of fibres coming 
from the anterior inferior spinous process of the ilium, (Ligament. As- 
cititium,) and descending, longitudinally, to the anterior oblique 
ridge of the os femoris. The internal and posterior portions of the 
capsular ligament are not so thick ; it is, indeed, very thin near the 
posterior ridge of the os femoris, being not more than half a line, and 
has a number of holes in it for the passage of vessels. It is strength- 
ened, internally, by some fibres coming from the superior margin of 
the thyroid foramen. 

This capsular ligament keeps the bones closely applied to each 
other, and is by no means so loose as the corresponding one of the 
shoulder joint. Its fibres are very irregular, generally, in their 
course, and difficult to follow. 

The strength of this articulation depends principally on the mus- 
cles which surround it, of which the rectus femoris, and the iliacus 
internus and psoas magnus united, are in front; between the latter 
two and the capsule, is a bursa mucosa. Within, are the pectineus 
and the obturator externus ; behind, are the quadratus, the gemini, 
the obturator internus, and the pyriformis ; above and behind, are 
the glutsei. 

The Synovial Membrane is a complete sac, displayed over the 
articular surfaces of the bone, and the internal face of the. capsule. 
It is separated from the roughness at the bottom of the acetabulum, 
by the existence there of a pad of very vascular, fine, fatty matter, 
from which, according to Bichat, it may be raised by blowing be- 

* Soemmering, De Corp. Hum. Fabrica. vol. ii. p. 61, 1794. Andrew Fyfe, 
Compendium of Anat. Philad. 1807, vol. i. p. 179. 

For an interesting account of the connexion of this capsule with the fascia 
femoris, see Anatomical Investigations, by J. D. Godman, M. D., Philad. 1824. 
The author, in following the sheaths of the muscles, or in other words, the 
processes of the fascia lata, between the muscles, to the capsule, with great 
attention, has been brought to the conclusion that the capsule is formed en- 
tirely from them. He has presented the same views in regard to the shoulder 
joint, and others. Though not disposed to concur in so general an inference 
on the source of capsular ligaments, inasmuch as their peculiar texture is op- 
posed to it, and many other circumstances in their anatomical arrangement, 
yet great satisfaction may be expressed at the fidelity with which these connex- 
ions of the larger joints have been traced. 



332 



SKELETON. 



neath the ligament of the notch, at the point where the blood ves- 
sels enter. Coming from the acetabulum, it covers the articular 
face of the cotyloid ligament, and is then reflected to the capsule, 
to which it gives a polished internal face, and from which it may be 
dissected. On reaching the root of the neck of the os femoris, it 
forms small duplicatures, and is reflected upwards along the neck to 
the head, being separated from the neck by periosteum, or by a 
fibrous tissue, which M. Boyer considers a continuation of the cap- 
sule. It covers all the head, except the point of attachment for the 
round ligament, and to the latter it gives a sheath, which, at the 
other end, is continuous with the part of the synovial membrane 
covering the fatty matter. From the latter circumstance, arises a 
deceptive appearance of the round ligament being inserted into the 
roughness in the bottom of the acetabulum.* 



Of the Knee Joint.] 

It is formed by the os femoris, the tibia, and the patella, the par- 
ticular modelling of whose articular surfaces, for the purpose, has 
been described. These surfaces are all covered by an uniform 
lamina of cartilage, and are held together by an apparatus which 
for the number of its parts and their arrangement, makes this the 
most composite joint in the skeleton. % - 

The most superficial layer of the knee joint is the fascia lata of 
the lower extremity, which, in passing down from the thigh to the 
leg, is so' near the cavity of the articulation on each side of the 

* Ihave found, in a first instance, Dec. 10, 1838, the capsular ligament of this 
joint with a large opening, nine by eighteen lines, in front, and the synovial 
membrane communicating through it with the bursa between the trochlea of 
the ilium and the iliacus internus muscle. A similar arrangement existed on 
both sides of the body, every thing else being normal. It was repeated in 
another subject, Jan. 2d, 1839, and has been observed in some instances 
since in our rooms. Such a condition must, of course, favour, under suitable 
circumstances, the internal dislocation of the os femoris. Two years and a- 
half ago, I was called to attend a child a year old, with this dislocation, but 
whose parents were ignorant of the period of its occurrence, and which had 
been, at any rate, some months previously. It appeared to me that the acci- 
dent might have been produced by some trivial fall, coincident, possibly, with 
this peculiarity. 

f Anat. Atlas, Figs. 120, 121, 122, 123. 



ARTICULATIONS OF THE LOWER EXTREMITIES. 333 

tendon of the patella, that it is by Weitbrecht spoken of under the 
term of Common Investment (Involucrum Generate.) It is here 
not only a continuation of the fascia femoris, but this fascia is in- 
creased and thickened by an aponeurosis, which springs from the 
inferior extremity of the extensor muscles on the thigh. The mem- 
brane thus formed covers both the patella and its ligament, and 
extends on each side to the lateral ligaments of the joint, to which 
it adheres; it may be traced even behind them, but there it becomes 
indistinct, loose, and blended with common cellular and adipose 
membrane. The involucrum adheres strongly to the internal and 
external condyles, and to the head of the tibia, from one lateral 
ligament to the other; it has oblique fibres on the patella, transverse 
ones on the ligament of the latter, and longitudinal ones on each 
side. It is in contact with the synovial membrane of the joint, 
except in the middle portion, where it is separated from it by the 
patella, and its tendon, and some adipose matter. It may be dis- 
sected without difficulty from the subjacent parts, by which the 
ligament of the patella, and the synovial membrane are brought 
into view. 

The Ligament of the Patella being situated at the fore part of 
the articulation, though separated from the extensor muscles by the 
intervention of the patella, is, nevertheless, their tendinous insertion 
into the leg. It arises from the whole inferior margin of the patella, 
and is inserted into the tubercle of the tibia. It consists in longi- 
tudinal, closely compacted fibres, of a character entirely tendinous; 
the more superficial of them give a layer to the front of the patella, 
and in the fracture of the latter sometimes prevent a separation of 
its fragments. In front, as just mentioned, it is in contact with the 
involucrum; behind, is a large mass of fat placed between it and 
the synovial membrane of the joint; and on the same surface, but 
lower down, it is in contact with a bursa mucosa fixed between it 
and the triangular flatness of the tibia above the tubercle. 

A posterior ligament, an internal and an external lateral ligament, 
two crucial ligaments, two semi-lunar cartilages, and a synovial 
membrane, compose the remaining apparatus of the joint. 

The Posterior Ligament (Lig. Posticum,) is a fibrous expansion 
on the back of the knee joint, which may be considered as the 



334 SKELETON. 

proper capsular ligament at this point, and has its fibres extending 
obliquely from the external condyle of the os femoris to the poste- 
rior part of the head of the tibia. It is frequently called the liga- 
ment of Winslow, and by the French anatomists is considered as 
one of the divisions of the tendinous insertion of the semi-mem- 
branosus muscle, in consequence of its close connexion with it. 
There are several foramina or interstices in it, which permit a 
passage of blood vessels to the fatty matter placed between it and 
the crucial ligaments; and beneath it there are some transverse 
fibres. 

The Internal Lateral Ligament (Lig. Laterah Internum) is a 
flattened fasciculus of fibres placed at the internal side of the joint. 
It arises from the tuberosity on the inner side of the internal con- 
dyle, and descending vertically is slightly attached to the inner 
semi-lunar cartilage, and is then inserted into the superior margin 
and the internal face of the head of the tibia for two inches or more, 
increasing in breadth as it descends. On the one side it is in 
contact with the synovial membrane, and on the other, with the 
involucrum and the tendon of the sartorius, the semi-tendinosus, 
and the gracilis. 

The External Lateral Ligament {Lig. Later ale Externum , Longum,) 
placed on the external side of the joint, is nearer its posterior face 
than the internal ligament. It arises from the tuberosity on the 
outer face of the external condyle, above and behind the tendi- 
nous origin of the popliteus muscle, and is inserted irrto the external 
part of the superior extremity of the fibula, being covered in almost 
its whole extent by the tendon of the biceps. Its inner face is in 
contact with the synovial membrane, and the articular vessels. Its 
rounded form and shining appearance make it look very much like 
a tendon. Behind it occasionally, is a small fasciculus, called by 
some the short external lateral ligament, which passes from the ex- 
ternal condyle to the head of the tibia. 

The Crucial Ligaments {Lig. Cruciata,) two in number, are 
named from their crossing one another laterally, and thereby form- 
ing a figure, resembling the letter X, or a Malta cross. They are 
situated at the posterior part of the articulation between the poste- 



ARTICULATIONS OF THE LOWER EXTREMITIES. 335 

rior ligament and the synovial membrane. One of them is called 
anterior, and the other posterior, from their relative situations to 
each other. The first arises from the internal face of the external 
condyle, by a depression near the posterior end of the notch and 
just at the margin of the articular surface ; it descends forwards, and 
is inserted immediately in front of the little ridge between the arti- 
cular faces of the tibia. The second arises from the bottom of the 
notch between the condyles, just behind the trochlea for the patella, 
upon a surface that may be considered as belonging to the internal 
condyle ; it descends backwards, and is inserted into the rough sur- 
face behind the aforesaid spine or ridge of the tibia. The crucial 
ligaments are large, round, and composed of parallel fibres very 
closely compacted ; their strength is very considerable, and they 
serve not only to limit the extension of the leg, but also to check 
any thing like rotation inwards. 

The Semilunar Cartilages (Cartilagines Semilunar es,Jalcatce,) are 
two in number ; one placed on either side of the superior face of the 
tibia, between it and the condyle of the os femoris. Their shape is 
sufficiently indicated by their names, and as they are placed on the 
circumference of each articular surface of the tibia, leaving the mid- 
dle uncovered, they increase considerably the depth of the con- 
cavities for receiving the condyles. Their external circumference 
is thick, whereas, the internal is reduced by a gradual diminution of 
their thickness, to a very thin edge. The internal cartilage is but 
little more than a semicircle, and is longer in its antero-posterior 
diameter than in its transverse ; on the other hand, the external is 
almost circular ; an arrangement by which each is suited to its re- 
spective surface. They adhere by their greater circumferences to 
the fibrous matter surrounding the joint, particularly the lateral liga- 
ments, but not so closely as to prevent their sliding backwards and 
forwards in the flexions of the leg. The tendon of the popliteus ad- 
heres to the external, either directly or by the intervention of a small 
synovial sac. 

The internal semilunar cartilage is attached by its fore extremity to 
the anterior internal side of the roughness in front of the ridge, called 
spinous process, on the top of the tibia, and by the hind extremity 
to the posterior face of the base of the ridge, just in advance of the 
posterior crucial ligament. The external cartilage is attached by its 
anterior end, also to the roughness in front of the ridge ; but this at- 



336 SKELETON. 

tachment is considerably behind the corresponding one of the inter- 
nal cartilage, and is somewhat blended with the anterior crucial 
ligament: the posterior end is fixed into the depression on the sum- 
mit of the ridge or spinous process, and is there between the two 
crucial ligaments. The anterior extremities of the two cartilages 
are united by a transverse ligamentous fasciculus a line in thickness, 
which is rather inconstant ; but when found, is in front of the anterior 
crucial ligament. These bodies, though presenting an appearance 
corresponding with cartilages, on their surface, are nevertheless, 
formed principally from concentric ligamentous fibres; the cha- 
racter of which is very evident at their extremities, and when 
they are lacerated. 

The Synovial Membrane is thin, loose, and delicate, and, as in 
other joints, is a perfect bag, covering the articular faces of the bones, 
and reflected from the one to the other. As there is no regular cap- 
sular ligament to the knee joint, the synovial membrane is very dis- 
tinct on each side of the tendon of the patella ; and comes in con- 
tact there with the fascia lata, or involucrum, as it passes from the 
thigh to the leg. The synovial membrane, after covering the articu- 
lar faces of the tibia, is reflected from their margin upon the semi- 
lunar cartilages, so as to invest their inferior and superior surfaces ; 
it then ascends to the condyles of the os femoris. It covers the con- 
dyles, laterally, as well as on their articular faces, and leaves 
thereby half an inch or more of their circumference on each side of 
the'trochlea of the patella, included in the periphery of the joint. 
The synovial membrane, anteriorly, being separated from the tendon 
of the patella, by the large mass of fat, then covers the posterior face 
of the patella, and rising up still farther, lines the posterior face of 
the tendons of the extensor muscles for the distance of three inches 
or thereabouts. The superior end of this reflection is formed into 
a small pouch communicating freely with the general cavity, but 
marked off from it by a partial and variable septum on each side. 
Some anatomists consider the pouch as a bursa, but it is so seldom 
seen entirely distinct from the joint, that it answers better to describe 
it as a part only of the general reflection. The synovial membrane, 
at the sides of the joint, is in contact with the lateral ligaments. Be- 
hind, it is reflected on the anterior surface of the tendinous origins 
of the gastrocnemius, and envelops the tendon of the popliteus ; 



ARTICULATIONS OF THE LOWER EXTREMITIES. 337 

it also invests the crucial ligaments, but in such a way as to leave 
them out of its cavity. 

The collection of fat behind the tendon of the patella forms, just 
below the latter, a ridge on each side, protruding into the articula- 
tion, and having a fringed summit formed by a doubling of the sy- 
novial membrane. The external ridge is the Ligamentum Alare 
Minus Externum, and the Other the Ligamentum Alare Majus In- 
ternum. These ridges converge at their lower extremities, and 
from their point of union proceeds a duplicature of the synovial 
membrane, in front of the anterior crucial ligament ; the other end 
of the duplicature is attached to the posterior extremity of the groove, 
in the middle of the trochlea for the patella. This duplicature is 
the Mucous Ligament, {Ligamentum Mucosum.) 



Of the Peroneo- Tibial Articulation. 

The tibia and the fibula are held together by three places of union, 
one above, another below ; and, thirdly, the ligament which fills up 
the space between the bodies of the bones. 

1. The Superior Articulation, formed by the upper extremity of 
the fibula and the outer side of the head of the tibia, is entirely dis- 
connected with the cavity of the knee joint, and has nothing in 
common with its apparatus, except the external lateral ligament, 
which has been described. The articular faces are small, and co- 
vered with cartilage ; an anterior and a posterior ligament, and a 
synovial membrane, hold the bones together at this point. 

The anterior ligament is attached by one end to the front of the 
head of the fibula, and proceeding upwards and inwards, is inserted 
by the other into the contiguous part of the head of the tibia, before 
the articular facet. The fibres are separated into fasciculi, leaving 
interstices between them for cellular substance. 

The posterior ligament is narrower than the anterior ; but its fibres 
are more compact, and, like the anterior, they observe a transverse 
course ; being attached by the one end to the head of the fibula, 
and, by the other, to the head of the tibia. The popliteus muscle 
covers it. This joint is also strengthened by other ligamentous 
fibres, and by the insertion of the tendon of the biceps. 

The synovial membrane is reflected over the articular faces and 
Vol. I.— 29 



338 SKELETON. 

the ligaments described, and has nothing of particular interest in it. 
Occasionally, the synovial membrane of the knee joint runs into it. 

2. The Inferior Articulation, which is formed between the lower 
extremities of the bones, is not incrusted by cartilage, except to the 
breadth of a line at its lower part, bordering on the ankle joint. 

Its anterior ligament is broad, and covers the face of the bones 
which are in apposition. Attached by the one side to the front of 
the lower extremity of the fibula, its fibres pass obliquely upwards 
and inwards, to be inserted into the corresponding part of the tibia. 
Several interstices exist in it for the passage of vessels, and it is 
covered by the peroneus tertius. Its lower margin is in contact 
with the astragalus, and forms a portion of the ankle joint. 

The posterior ligament, in the arrangement and course of its fibres, 
corresponds with the anterior; being attached by one side to the 
posterior face of the fibula, and by the other to the corresponding 
part of the tibia. Like the other, its fibres are longer near the ankle 
joint than above. Its lower margin is in contact with the astragalus, 
and is connected with other ligaments coming from the fibula. 

In the space between the anterior and the posterior ligament, 
where the bones touch, they are agglutinated by a short, strong, 
fibrous tissue, leaving intervals occupied by adipose matter. It 
contributes much to the solidity and immobility of this articula- 
tion. 

3. The Interosseous Ligament {Membrana Interossea,) is ana- 
logous to that in the fore arm, by being a membrane stretched be- 
tween the two bones. It arises from the ridge on the outer face 
of the tibia, and is attached to the corresponding ridge on the inner 
face of the fibula. It is broader above than below, being at the 
latter point continuous with the fibrous structure which aggluti- 
nates the bones. Just below the head of the fibula is a large hole 
for transmitting the anterior tibial vessels, and the origin of the 
tibialis posticus muscle. It also presents, in its descent, several 
smaller foramina for the passage of vessels. Its fibres are strong 
and unyielding, and run obliquely downwards from the tibia to the 
fibula. It is covered in its whole length, both before and behind, 
by muscles, and serves as an origin to them and as a means of 
attachment between the bones. 



ARTICULATIONS OF THE LOWER EXTREMITIES. 339 



Of the Ankle Joint* 

The articular surfaces, here, being covered by cartilage as in 
other moveable joints, are formed by the astragalus being received 
into a deep cavity made by the tibia and the fibula. The capsular 
ligament, properly speaking, does not exist either on the front or 
the back of the joint, and is represented, there, by a few scattered, 
loose fibres, on the periphery of the synovial membrane. An inter- 
nal and an external lateral ligament, with the synovial membrane, 
constitute the whole apparatus. 

The Internal Lateral Ligament, also called the Deltoid, (Lig. 
Deltoideum) arises from the whole inferior margin of the malleolus 
internus, and with particular strength from the depression which 
exists in it: it then descends and is inserted into the internal face of 
the astragalus, and into the lesser apophysis of the os calcis, which 
lies just below it, being also strongly attached at its anterior part 
to the Internal Calcaneo-Scaphoid Ligament. This internal lateral 
ligament is broad, thick, quadrilateral, and composed of fibres 
which descend obliquely backwards. The tendon of the tibialis 
posticus runs in a trochlea which is formed on the internal face of 
this ligament. 

The External Lateral Ligament (Lig. Triquetrum) consists in 
three distinct fasciculi, of which one is anterior, another posterior, 
and the third in the middle. The anterior arises from the lower 
extremity of the malleolus externus, and running inwards and for- 
wards, is inserted into the outer face of the astragalus in front of 
the surface for the fibula. The posterior arises from the depression 
in the extremity of the malleolus externus, and, running inwards 
and backwards, is attached to the point of the astragalus, at the 
outside of the groove, for the tendon of the flexor pollicis pedis. The 
middle arises from the pointed termination of the malleolus externus, 
and, descending beneath the tendons of the peronei muscles, is 
attached to the external face of the os calcis, below the surface for 
the astragalus. These fasciculi are composed of strong longitudinal 
and parallel fibres. The posterior is larger than either of the others, 

* Anat. Atlas, Figs. 124, 125, 126. 



340 



SKELETON. 



and occasionally detaches a part which is inserted into the posterior 
margin of the articular face of the tibia. 

The Synovial Membrane is reflected, as usual, over the articular 
surfaces, and from one bone to the other. It sends up a short pro- 
cess of a line in length between the tibia and the fibula, it is re- 
markably loose in front and behind, and has on its superficial face 
a considerable quantity of adipose matter, which cannot be easily 
detached from it. It commonly contains an unusual quantity of 
synovia. 

Of the Articulations of the Foot* 

Of the Tarsal Articulations. — 1. The Os Astragalus is united 
to the Os Calcis by a double articular surface, which has been 
described. The ligaments which hold them together are as fol- 
low,: — 

The Interosseous Ligament is placed between the two bones, so 
as to occupy the large oblique fossa between the double articular 
surface in each. It is a collection of very strong, short fibres, with 
interstices for fatty matter, and, which, arising from the whole length 
of the groove in the astragalus, descends to be inserted into corres- 
ponding points in the groove of the os calcis. Where the fossa is 
narrow, as it is behind, the ligament is thin and flat, but it augments 
considerably in front, where there is more room for it. 

The Posterior Ligament arises from the posterior margin of the 
astragalus, and, descending obliquely inwards, is inserted into the 
adjacent portion of the os calcis. Its fibres, are blended with those 
of the Deltoid Ligament, and on their posterior face they form a 
ligamentous trochlea for the tendon of the flexor longus pollicis 
pedis. 

This articulation is also strengthened by the insertions stated, of 
the lateral ligaments of the ankle joint into the os calcis. 

The Synovial Membrane forms a distinct cavity on the posterior 
and larger articular face of the two bones, and is in contact with, the 
fatty matter in advance of the tendo-achillis. 

* Anat. Atlas, Figs. 127, 128. 



ARTICULATIONS OF THE LOWER EXTREMITIES. 341 

2. The Articulation of the Astragalus with the scaphoides is 
formed by the convex head on the part of the former, and by the 
concavity on the part of the latter. It is covered, above, by a thin, 
broad ligament, with parallel and oblique fibres, which, arising from 
the superior and internal face of the astragalus, are implanted into 
the upper face of the scaphoides, some of its fibres extending over 
to the cuneiform bones. It is covered, above, by the tendons of the 
extensor muscles of the toes, and of the tibialis anticus. 

On the under surface of the foot, this articulation is supported by 
two ligaments, called the Calcaneo Scaphoid, (Lig. Plana,) from 
their origin and insertion. The Internal one arises from the inter- 
nal margin of the lesser apophysis of the os calcis, and, running ob- 
liquely forwards and inwards, is inserted into the under and internal 
surface of the os scaphoides. It is a very thick, flattened fasciculus, 
on the under surface of which is formed the ligamentous trochlear, in 
which run the tendons of the flexor longus pollicis and flexor longus 
digitorum, and which surface is also in contact with the tendon of 
the tibialis posticus. By subtending the head of the astragalus, the 
Internal Calcaneo Scaphoid Ligament contributes largely to keeping- 
it in place, in the erect position. The External Calcaneo Scaphoid 
Ligament, placed at the outer margin of the last, arises from the 
under surface of the greater apophysis of the os calcis, and running 
obliquely inwards and forwards, is implanted into the under exter- 
nal surface of the scaphoides. It consists in two or more short, 
strong fasciculi. 

The Synovial Membrane of the articulation between the astragalus 
and the scaphoides covers the articular faces of these bones, and 
lines the ligaments above and below. A reflection of it, also, lines 
the articulation between the os calcis and the astragalus, in front of 
the rough fossa which is occupied by their interosseous ligament. 

3. The Calcaneo Cuboid articulation, formed by the two bones 
indicated in the name, is maintained by two ligaments, one above, 
the other below, and by a synovial membrane. 

The Superior Calcaneo Cuboid Ligament arises from the upper 
anterior surface of the os calcis, and is inserted into the adjoining 
upper surface of the cuboides. It is broad, thin, and quadrilateral 

29* 



342 SKELETON. 

with short parallel fibres, and is in contact, above, with the peroneus 
tertius tendon. 

The Inferior Calcaneo Cuboid Ligament, (Lig. Pldntare,) placed 
on the plantar surface of the foot, is remarkable for its size and ex- 
tent. It consists of two horizontal planes of fibres, of which the 
superficial is the longest. The latter arises from the back under 
surface of the os ealcis, and, advancing forwards, its fibres are in- 
serted into the summit of the ridge which traverses the cuboides 
obliquely ; the greater part of them, however, go beyond this point, 
and, dividing into fasciculi, are inserted into the base of the fourth 
and fifth metatarsal bones. The tendon of the peroneus longus is 
confined between these fasciculi and the under surface of the cu- 
boides. The other plane of this ligament being more deeply seated, 
is also shorter. It arises from the front under surface of the os ealcis, 
where the tuberosity exists at this point, and, by advancing, is in- 
serted entirely into the oblique ridge of the cuboides. 

The Synovial Membrane being reflected over the articular surfaces 
of the bones, and lining the ligaments, is uncovered at several places 
above, where interstices exist between the fibres of the superior 
ligament, and externally it is contiguous to the tendon of the pero- 
neus longus. 

4. The Scaphoid and the Cuboid bones touch at the external pos- 
terior angle of the cuneiforme externum, and form, there, occasion- 
ally, a distinct articular surface, with a synovial membrane. Be- 
sides this mode of union, an interosseous ligament is introduced 
between them. On the dorsum of the foot there is a transverse liga- 
ment running from one bone to the other beneath the extensor ten- 
dons ; and on the sole of the foot there is an oblique ligament, which, 
arising from the under surface of the scaphoides, is inserted into the 
anterior internal margin of the cuboides. 

The articular surfaces of the Cuboides and Cuneiforme Externum, 
which are in contact, besides a distinct synovial membrane, are 
secured by transverse and oblique ligamentous fibres going from the 
one bone to the other. 

5., The Articulation between the scaphoides and the three cunei- 



ARTICULATIONS OF THE LOWER EXTREMITIES. 343 

form bones is secured by a dorsal and a plantar ligament. The 
dorsal, arising from the back of the scaphoides, is divided into three 
fasciculi, that go respectively, to the back of each cuneiform bone ; 
of these, the internal is the strongest, and is particularly well marked 
on the internal face of the cuneiforme internum. The plantar liga- 
ments are, also, three in number, and having a sort of common base 
from the under surface of the scaphoides, by being divided into three 
fasciculi, as the above, are inserted into each cuneiform bone. They 
are not so well marked as the upper ones. 

The cuneiform bones are also connected together above and be- 
low, by short transverse ligaments going from one bone to the 
other, and holding their lateral surfaces in contact. Those below 
are not so distinct as the upper ones, and are blended with the inser- 
tions of the tibialis posticus. 

One synovial membrane covers the articular surfaces of the sca- 
phoides and of the cuneiform bones which are in contact ; and it 
extends itself by digital processes between the first and second, and 
the second and third cuneiforms, so as to line also the articulations 
there. The process between the latter two is much shorter than the 
process between the former two, which extends itself into the tarso- 
metatarsal articulations, after the same principle which is observa- 
ble in the hand. 



Of the Tarso-Metatarsal Articulations. 

The articular faces of the bones, here, having been sufficiently 
described, it is to be noted in addition, that besides being covered 
with cartilage, they have the apparatus of the moveable articulations 
generally, in ligaments which hold them together, and in synovial 
membranes. The ligaments are above and below. 

1. The articulation of the first metatarsal bone with the cunei- 
forme internum is one third of an inch in advance of the next, and 
completely insulated by its synovial membrane: it is strongly secured 
by ligamentous fibres above, internally and below, which give it 
almost a complete capsule.. 



344 SKELETON. 

2. The dorsal or upper ligaments of the remaining metatarsal 
bones are arranged as follows. There are three for the second 
metatarsal ; one comes from the second cuneiform, one from the 
first, and another from the third ; the latter two are oblique ; and 
they all converge to be inserted into the base of the bone to which 
they belong. One dorsal ligament passes from the third cuneiform 
to the base of the third metatarsal ; it is sometimes assisted by a fas- 
ciculus from the cuboides. From the superior face of the cuboid 
bone a fasciculus is sent to the base of the fourth and fifth meta- 
tarsals. 

The plantar or under ligaments are arranged on the same plan 
with the dorsal. Not being quite so strong, they are re-enforced 
by the fibrous sheaths of the flexor tendons which lie upon them. 

The synovial membrane, which is reflected over the articular 
surfaces between the second and third metatarsals and their cor- 
responding cuneiforms, is the elongation of the digital process sent 
from the scaphoid articulation between the first and second cunei- 
forms. This process, besides extending to the aforesaid tarso- 
metatarsal articulations, insinuates itself to the articular surfaces on 
the sides of the second metatarsal bone ; but a distinct synovial cap- 
sule is sometimes formed between the base of the third and fourth 
metatarsals. 

One synovial membrane is reflected over the surfaces, between 
the cuboides and the last two metatarsals, and sends in a process 
between the latter. In all these cases the synovial membranes line 
the dorsal and plantar ligaments of their respective articulations. 



Of the Metatarsal Articulations. 

The metatarsal bones, with the exception of the first, articulate 
with each other by the contiguous faces of their roots, as has 
just been stated; along with the manner of their getting at these 
points, a lining of synovial membrane. They are farther fastened 
to each other by short transverse ligamentous fasciculi, which pass 
from the base of one to the base of the adjoining. These fasciculi 
exist both on the upper and under surface of the bones, are, there- 



ARTICULATIONS OF THE LOWER EXTREMITIES. 345 

fore, denominated dorsal and plantar metatarsal ligaments. There 
is also a description of interosseous ligament between the bases of 
these bones, occupying the space intermediate to the dorsal and 
plantar ligaments of each. 

The anterior extremities of the metatarsal bones are not in con- 
tact; they are, however, fastened to each other by a transverse or 
Anterior Plantar Ligament on their under surface, the fibres of 
which are somewhat blended with the capsular ligaments of the 
first joints of the toes. 



Of the First Joints of the Toes. 

The surfaces of the bones here being covered with cartilage, are 
formed into an arthrodial articulation. There is a fibrous capsule 
surrounding the articular faces, and enclosing the synovial mem- 
brane. This capsule is considerably thickened below, where the 
flexor tendons pass over it; above, it does not exist, as the extensor 
tendon is there lined by the synovial membrane : on each side it is 
also thickened, so as to form a lateral ligament, but much weaker 
than the corresponding ligament of the fingers. In the great toe 
the external lateral ligament is frequently inserted into the outer 
sesamoid rather than into the first phalanx. In the under part of 
the capsule of the great toe, we find on each side a sesamoid bone. 

These joints resemble so strongly the corresponding joints of the 
fingers, that a farther description is unnecessary. 



Of the Second and Third Joints of the Toes. 

From the shape of the surfaces of the bones composing them, 
these are simply ginglymous articulations. They have their car- 
tilaginous incrustations, synovial membrane, and capsular ligament. 
The under part of the latter is much thickened, and forms a trochlea 
for the flexor tendons; on each side it is arranged into a lateral 
ligament, and above it is defective, as the synovial membrane is in 
contact with the extensor tendon. These joints also resemble so 
strongly the corresponding ones of the fingers, that farther description 
is unnecessary. 



BOOK II. 



OF THE INTEGUMENTS OF THE BODY. 

The integuments of the body consist in the Cellular and Adipose 
Substance, and in the Dermoid Covering. 



PART I. 

Cellular and Adipose Substance. 
CHAPTER I. 

Of the Cellular Substance.* 

The Cellular Substance (Textus Cellulosus, Mucosus) also called 
Areolar Tissue is an elementary one, and is more generally diffused 
than any other of the body, for it seems to be quite as indispensable 
to the latter as the corpus mucosum is to vegetables. It is found 
abundantly beneath the skin; between muscles; in the interstices of 
muscles and of other parts; connecting membranes to one another; 
surrounding organs; entering into their composition; glueing them 
together; in fine, under every variety of circumstance and locality 
of which the human organization admits. Indispensable as it is to 
the texture of all other parts, we find it, as may be expected, pre- 
ceding them in the development of the foetus; at which period it is 
in the condition of a fluid slightly coagulated. 

When examined with a microscope, as it winds around a muscle 
and introduces itself between the fasciculi of its fibres, it will be 
seen that, however fine the latter may be, yet this tissue is inter- 
posed between them in thin laminae. On separating these fibres, 

* Anat. Alas, Fig. 131, 



348 INTEGUMENTS. 

the intervening laminae are resolved or drawn out into fine filaments, 
which, finally, break after being stretched to a certain extent. The 
lamina which surrounds the whole body of the muscle, and con- 
stitutes its sheath, on being put upon the stretch, tears only after 
having been attenuated into still thinner laminae and into fibres. 

If air be blown into the sheath of a muscle, this sheath is dis- 
tended into a multitude of cells of various forms and sizes, which 
have no determined shape, and do not upon the expulsion of the air 
return to the same shape upon a repetition of the inflation. Such 
cells communicate very freely; all limpid fluids pass with the 
greatest ease from one to the other, so that from any single point 
they may, by the force of injection, be distributed throughout the 
body; this is manifested in emphysema, where from a small wound 
in the thorax, air becomes universally diffused. Fluids of any kind, 
except they be inspissated, when deposited in these cells, are sub- 
ject to the common laws of gravity, and continue to descend suc- 
cessively from the higher to the lower cells, as in anasarca. Blood 
traverses them very readily in ecchymosis. 

Cellular tissue enjoys a good deal of elasticity, for when stretched 
it readily returns upon itself. When very thin, as between the 
fibrillae of muscles, it is colourless or nearly so, and of a gelatinous 
or glue-like consistence ; but when its laminae are thicker, it is of 
an opaque white, and has a strength amounting almost to that of 
ligamentous matter. When dried it becomes crisp and of a dark 
brown; but may be restored to its colour and condition by soaking 
in water. It is only very slightly affected by the usual heat of the 
culinary processes of roasting or boiling, as our dishes of meat daily- 
prove; but maybe resolved into gelatin after a protracted ebullition. 
Its putrefaction is slow„and cannot be accomplished, by maceration, 
under several months. 

The cellular substance is pervaded by a large number of blood 
vessels, the majority of which do not, in a natural state, convey 
obviously red blood; but if any portion of it be exposed for a short 
time to the air, or to any other unusual stimulus, it quickly becomes 
suffused with red blood, circulating through an infinitude of channels. 
It cannot, however, be conceded, as Ruysch supposes, that it is 
formed exclusively of blood vessels. Some anatomists, indeed, 
as Haller and Prochaska, allow that though blood vessels ramify 
through it, yet they are not spent upon it, or do not form a part of 
its organization. The distinction is rather too subtle, to be readily 



CELLULAR SUBSTANCE. 349 

admitted, and seems, moreover, to be refuted by the continued ex- 
halation and absorption which is going on within. It does not 
appear that nerves are spent upon the cellular substance, though 
they pass abundantly through it to their respective organs. 

It is probable that the granulations upon which injured parts of 
the body depend for their restoration, arise from this cellular sub- 
stance. The late Professor Wistar attended a patient for compound 
fracture of the leg, with a large wound, which was subsequently 
covered with luxuriant granulations. The limb was suddenly at- 
tacked with an cedematous swelling, which extended itself to the 
sore, and caused its granulations to tumefy, so that they pitted upon 
pressure precisely like other parts.* 

The most generally received opinion of anatomists, f in regard to 
the arrangement of cellular tissue is, that it results from the assem- 
blage of a multitude of lamellse, and of fine soft filaments, which 
being variously interwoven, produce a series of cells all communi- 
cating one with another, but varying in their shape and size ; so that 
the whole cellular substance may be considered to represent a single 
cavity subdivided into an infinitude of smaller ones. To this it is 
objected,^ that when this tissue is accurately examined, it appears 
rather as a homogeneous, viscid, and only partially solidified sub- 
stance ; particularly in the inferior orders of animals, and in the em- 
bryo state of the more exalted, where it has still to admit the depo- 
site or formation of the several organs. That the same is manifested 
at any period of life ; for neither with the naked or assisted eye does 
it assume any other appearance. That its laminated and filament- 
ous condition, when such does appear, is owing to its glutinous or 
glue-like consistence, which causes it to assume a factitious arrange- 
ment upon being drawn or inflated. For example, if one separates 
two muscles for a short distance, the cellular substance between them 
becomes unequal and furrowed without losing its cohesion; but If 
they be farther separated, filaments and cylindrical columns are pro- 
duced. If the traction be then suspended, and the muscles replaced, 

* System of Anat. vol. i. p. 388, 2d edition, 
f Haller, Beclard, Bichat, Wm. Hunter, &c. 

% Bordeu, Recherches sur le Tissu Muqueux et Celluleux. Paris, 1790. 
J. F. Meckel, Manuel D'Anat. vol. i. p. 105, 
Vol. I.— 30 



350 



INTEGUMENTS. 



the filaments shorten, and are finally united into a consistent mass 
whose parts all adhere together.* 

While such tractions are going on, it most frequently happens that 
air is insinuated into the cellular substance, from which comes the 
appearance of small cells and vesicles; upon the escape of this air, 
the primitive state of cohesion is restored, and upon a renewal of 
the traction, cells of a different shape, size, and appearance arise. 
Again, if air be so introduced, one may push it in any direction, se- 
parate its globules, collect them again, and into larger masses ; vary 
their shape, and, in fine, by such means mould the supposed cells 
into an infinity of forms. From these considerations, the inference 
is plain, that when cellular substance is drawn it must yield itself 
into filaments ; when inflated as the air acts in every direction, its 
supposed lamellae must be separated and assume a cellular shape ; 
and, by the application of both forces at once, it may be caused to 
assume both a cellular and a filamentous appearance. Upon the 
whole, Meckel conceives that the term Mucous Tissue, adopted by 
Bordeu, is much more exact than the one of Cellular Tissue, now 
most generally used. 

Notwithstanding the general similarity of cellular substance where- 
ever found, there is a w r ell marked difference between portions of it, 
for example, the intermuscular and subcutaneous cellular substance, 
when inflated and dried, remains permanently lamellated, whereas, 
that which makes a regular tunic to the alimentary canal and other 
hollow viscera, when treated by the same process is permanently 
filamentous and resembles so much carded cotton, that at a little 
distance their appearance is almost identical. The lamellated is also 
much more glutinous to the feel and sight than the filamentous. The 
filamentous cellular substance is in its normal condition free from fat 
cells, a disposition indispensable to the preservation of the cavities 
to which it belongs. 

The cellular tissue like all others pre-exists in the condition of a 
homogeneous formative mass called cytoblastema, which corresponds 
in animals with the gum so abundant in the nascent parts of plants. 
This gum or cytoblastema appears to become, according to the ob- 
servations of Schleiden,f turbid from the presence of minute mole- 
cules. In a short time larger molecules are noticed. These se- 

* J. F. Meckel, loc. cit. 

f Miiller's Physiology, p. 49. Bell's Edition. 



CELLULAR TISSUE. 351 

condary molecules augment in size by agglomeration or coagulation, 
and in that state constitute cytoblasts, in which the secondary 
granules are visible as nuclei. A cytoblast finally reaches its full 
size, and then a small vesicle appears on it, which enlarges and be- 
comes a cell. The cytoblast is more or less permanent, and is for 
some time visible either attached to the interior of the cell or free 
in its cavity. The observations of Schwann are admitted to have 
proved the exact identity, of the process described, as compared in 
plants and in animals. The process of primitive evolution, therefore, 
in every case exhibits the stages of nucleoli, nuclei or cytoblasts, and 
germinal cells surrounding the latter. Mirbel had previously shown 
that the ultimate form of all vegetable tissue, was that of cells. 

In the earlier stages of the cell it bears the relation to the cyto- 
blast which a watch glass has to the watch, but finally enlarges so 
as to enclose it. Some nuclei are permanent, but others finally dis- 
appear entirely. The cells thus formed have others developed in 
their interior, which by their reciprocal pressure become polyhe- 
dral.* The cells of cellular tissue pass from the above nascent state 
into one of an elongated spindle-like shape, having its extremities 
resolved into fine filaments. The filamentous structure finally invades 
the whole cell except the nucleus, and the transformation is now com- 
plete by its running into similar adjoining filaments. 

Dr. M. Barryf advances the opinion that the blood corpuscles or 
globules are the nuclei or cytoblasts of the primitive cells, from 
which all the animal tissues arise. The crystalline lens he considers 
one of the best proofs of this conversion. 

Notwithstanding the perfect continuity of the mucous or cellular 
substance throughout the body, anatomists for the ease of description 
have divided it into External and Internal. 

The External Cellular Substance (Textas Cellulosus Intermedins, 
seu Laxus) has the general extent and shape of the body and of its 
organs, so that if it were possible to extricate the latter from their 
envelope, it would present a chamber for the lodgment of each part. 
But the walls of these chambers would not all be of the same thick- 
ness, as the quantity of cellular substance varies. In the cranium 

* The above subject has also been treated of with great perspicuity by 
Valentin, who has investigated closely these primordial laws of growth. See 
Bells's Muller, p. 114. 

f Phil. Trans., 1840-41. 



352 



INTEGUMENTS. 



and spinal cavity there is very little of it : on the surface of the head 
and in the orbits more : about the trunk, both internally and exter- 
nally, it is abundant ; in the extremities still more so, where it pene- 
trates between the muscles. In the arm pit, in the groin, and in the 
neck, all parts where much motion is enjoyed, it is unusually abun- 
dant. The foramina of the cranium and of the spine, establish the 
points of connexion of the cellular substance of these parts with 
others adjacent. The cellular substance of the face is continued 
into that of the neck ; that of the latter is continued through the 
upper opening of the thorax upon the viscera of this cavity ; and 
thence through the openings of the diaphragm, along the great ves- 
sels and oesophagus upon the viscera of the abdomen and pelvis. 
The cellular substance of these cavities is again continuous with the 
deep-seated cellular substance of the limbs at the arm pit and at the 
groin. The trunk of the body being enveloped by one broad sheet of 
cellular substance, it is continued superficially to the limbs.* 

With this general sketch of the distribution and extent of cellular 
substance, it is not surprising that in certain bad cases of emphy- 
sema, the air shows itself every where, even at points the most re- 
mote from the lungs, and apparently the least exposed to the acci- 
dent, as the interstices of muscles, of glandular organs, and so on. 
It will also now be understood how this varied distribution of cellular 
substance and its proteiform shape, have been the inexhaustible but 
delusive source of anatomical discoveries and supposed novelties, 
under the name of fascia?, sheaths of vessels, and so on ; and will 
continue to be so, to such as do not recollect that all these things 
are included under the general character of this tissue ; and that 
each muscle, each viscus, each nerve, and each blood vessel, has its 
own particular chamber under this multiform arrangement, which 
chamber may be traced to or from any other point, according to 
fancy. At the same time it should be noted that many of the lami- 
na? have a condensed form, which renders a special knowledge of 
them of the greatest use to the surgeon, and which is elsewhere 

* For a detailed account of the inflections of the cellular suhstance, the 
student may consult with advantage, Bordeu, loc. cit. These inflections are 
the Fasciae of the more modern, Surgical Anatomy. 

Bichat, Anatomie Generale ; Systeme Cellulare. Paris, 1818. 

Andreas Bonn,"de Continuationibus Memhranarum, in Sandifort's Thesaurus 
Dissertationum, Rotterdam, 1769. 

Haller, Element, Physiol, vol. i. 1757. 



CELLULAR SUBSTANCE. 353 

succinctly pointed out, with the description of their respective 
organs. 

Anatomists who lived at a period much less illuminated than the 
present on the subject of the elementary tissues of the body, seem to 
have seized upon the idea of the universal inflection of cellular sub- 
stance over the surface, and through the texture of the several 
organs. Mangetus,* without pretending to originality, but in 
alluding freely to the observations of others, says, "Membrana adi- 
posa, est expansio cellulosa, quae totum corporis habitum, paucis- 
simis, iisque minimis partibus exceptis, circumambit; et in qua 
materia albicans unctuosa, sensu expers, ad partes fovendas ac lu- 
hricandas colligitur. — Hsec membrana cellulosa seu pinguedinosa, 
non tantum in exterioribus corporis reperitur ; sed interius in intes- 
tinis, mesenterio, aliisque prope omnibus partibus, non exceptis 
etiam vasis sanguiferis, ut suo loco videbimus, observatur." And 
in describing the aponeurotic covering of the body and of the limbs, 
which in his day was called Membrana Musculosa, from some false 
notions of its nature, he adds, " Dicitur oriri a dorsi vertebris, quia 
scillicet earum spinis firmiter adhseret, inibique multo quam alibi 
usquam robustior conspicitur. Usus est, musculos universim in 
sua sede firmare, iisque quasi thecam prsestare, in qua ut supra in_ 
nuimus laxius sibi eohserente, lubrice moveriqueant." The cellular 
investments of the muscles the same author calls Membrana Mus- 
culi Propria, and he speaks of their penetrating between the fasciculi 
of muscles, and most evidently those of the glutseus magnus and 
deltoides. 

The Internal Cellular Membrane ( Textus Cellulosus Stipatus) pre- 
sents itself under different arrangements according to the organ or 
part whose interstices it penetrates. As it forms in the muscles an 
envelope for each fasciculus and fibre, if the latter by any art could 
be withdrawn, it would represent a congeries of fine parallel tubes. 
In the case of glandular bodies the internal cellular membrane imi- 
tates the shape of their lobes, lobules, and acini or small graniform 
masses, and may, therefore, be compared to a sponge. In the hol- 
low viscera, as the stomach and bladder, it unites their successive 
laminae to one another. In the ligaments, even where the fibrous 
structure is perfectly evolved, the fibres are united by cellular tis- 

* Theatrura Anatomicum, Geneva, 1716, vol. i. Ch. iii. 
30* 



354 INTEGUMENTS. 

sue in their interstices. This tissue is not sufficiently abundant in 
the bones, tendons, or cartilages, to be very distinct ; but from what 
is seen of it in the forming stage of the embryo, it is nevertheless 
ascertained to be the base of every part. In glandular textures 
it is frequently spoken of under the name of parenchyma in connex- 
ion with their acini. 

Most of the membranous textures of the body may by maceration 
be resolved into this pulpy or cellular tissue, so that we hear ana- 
tomists, without hesitation, asserting, that under various degrees of 
consistence, it forms the skin, the serous membranes, the vessels, 
the ligaments, in short, almost every thing excepting the bones, the 
muscles, the nervous system, and the glands, and they only depart from 
it in having their globules deposited in its interstices.* Meckel even 
adds to the list the epidermis. 

The term mucous tissue was substituted for that of cellular, by 
Bordeu, f owing to its glue-like consistence, and to its resemblance 
to the corpus mucosum of vegetables. Notwithstanding its pro- 
priety on these grounds, yet as the lining membrane of all the hollow 
viscera has the same name, some confusion may be produced unless 
one bears in mind the distinction. Bordeu has expressed the cha- 
racter of the internal cellular membrane very forcibly in saying, that 
in embryos all their organs are species of buds, which vegetate in 
the cellular tissue, like plants do in the open air, or their roots in 
the ground, and that each one having an apartment of its own, this 
apartment is to it a cellular atmosphere, which keeps in a perfect 
relation with the action of the organ.} 

In tracing many of the lamina; of the cellular substance, we find,, 
that as life advances, they assume a more fibrous character than 
what they possessed in infancy; this also occurs when tb.ey are 
pressed upon by tumours, or irritated from many other causes. 
This disposition of the cellular substance to assume a ligamentous 

* Beclard, Anat. Gen. p. 141. Kaller, loc. cit. p. 19 ; vol. L p. 113- 

f Loc. cit. 

\ Loc. cit. p. C5. Recherches Anatomiques sur les Glands, Paris, 1752.. 
Also, an Exposition of the Physiol, and Pathol. Doctrines of Theoph. Bordeu, 
understood to be from the pen of a learned friend, R. La Roche, M. D., in the 
North American Med. and Surg. Journal. Philad. April, 1826. 



CELLULAR SUBSTANCE. 355 

character, in many of the attachments which are formed between 
the two tissues, frequently leaves it doubtful with which the mem- 
brane under examination should be classed ; in some individuals 
the fibrous substance is predominant, and in others the cellular. 
This deposite of fibrous matter into cellular substance, or rather 
the change of the latter into it, may be compared to the partial or 
even perfect conversion of the cartilages of the thorax into bone 
by an increased deposite of the phosphate of lime. It perhaps will 
be better understood by repeating that this cellular tissue is an ele- 
mentary one, whereas, the ligamentous is composed of it and liga- 
ment. 

In addition to the uses of the cellular substance in forming a nidus 
for the deposite of all the molecules of the body, and in circumscribing 
each organ, so as to keep it distinct from the contiguous ones of a 
different character, its elasticity and yielding nature permit it, in 
the movements of the several parts upon each other, to change its 
position, and upon the cessation of the active cause, to re-establish 
itself. Its extreme flexibility is kept up by a continued exhalation 
of moisture from the arteries that ramify through its texture. This 
cellular serosity, when an animal is recently killed, and its internal 
parts exposed to a cold atmosphere, rises in the form of vapour, and 
has a particular smell. It is more abundant in certain parts than 
in others; and, as a general rule, where there is the least adipose 
matter. Indeed, these two substances seem to exist in an inverse 
ratio: in a person, for example, who has died very fat, the parts 
are comparatively dry ; whereas, in such as have all the adipose 
matter wasted by a lingering disease, there is a humidity which 
quickly disposes to putrefaction ; a fact frequently exemplified in 
our dissecting-rooms. The cellular serosity is, consequently, more 
abundant in the scrotum, in the eyelids, and in the penis. Bichat 
informs us, that he has satisfied himself by experiments, of its aug- 
mentation during digestion, during heavy perspirations, and after 
sleep ; which will account for the swelling of the eyelids, so com- 
monly observed in the morning, upon rising. 

This serosity is albuminous, as proved by its being coagulated 
by alcohol, and by the mineral acids. It is removed by the absor- 
bents; assisted by the tonic contraction of the cellular membrane, 
according to M. Beclard.* The latter author, indeed, goes on to 

* Anat. (Sen. p. 149v 



356 



INTEGUMENTS. 



say, that the cellular membrane is the essential organ of absorption, 
by which the skin and the villosities of the internal membrane of 
the hollow viscera perform this function. That the substances in- 
troduced through it into the blood vessels, no doubt, in doing so, 
undergo some kind of elaboration, in the same way that those do, 
which are deposited in its interstices for the growth, repair, and 
changes of the body. 



CHAPTER II. 

Of the Fat, (Adeps.*) 

The Adeps, in subjects not much emaciated, is found beneath the 
skin, between it and the fascia: ; and in the layers of common 
cellular substance which are next to the muscles : as on the face, 
the neck, the trunk of the body, the buttocks, the limbs, the palms 
of the hands, and the soles of the feet. In the adult, it is also found 
between the serous membranes and the cavities which they line, 
as in the thorax and abdomen; it is also found between the lamina 1 
of these membranes, as in the omenta, mesentery, and so on. It, 
likewise, exists between the interstices of muscles ; in the bones, 
and elsewhere; so that its whole amount is estimated at about one- 
twentieth of the entire weight of the body. There are, however, 
certain portions of the body, where its presence would have been 
very inconvenient: they, accordingly, are destitute of it; to wit, 
the interior of the cranium, of the ball of the eye, the nose, the ear, 
the intestinal canal, the eyelids, the scrotum, the penis, the labia 
interna, and the substance of the glands. 

The adeps is of a yellowish colour, and of a semifluid state in 
the living body: when after death it has got a few degrees below 
the standard of animal heat, it becomes somewhat solidified, and 
then appears in small aggregated masses of different shapes and 
sizes. 

In chemical composition it differs from all other parts of the body 

* Anat. Atlas, Figs. 132, 133, 134. 



ADEPS. 



357 



by the absence of nitrogen, and is formed of oxygen, hydrogen, and 
carbon, which render it, in animals, a very suitable article for can- 
dles and lamps. According to the analysis of Chevreul,* it consists 
of two kinds of matter, Elainand Stearin ; the former of which remains 
fluid at the freezing point, while, as mentioned, the other becomes 
solid by a very small abatement of its living temperature. The ap- 
plicatfon of porous paper enables one to separate them in a small 
way. Strong mechanical pressure does the same thing, and is now 
much used in the United States in the manufacture of lard oil for 
domestic purposes. 

The substance called Margarine, also exists in most fats, and is 
the principal constituent of the human ; hence the comparative soft- 
ness of the latter to mutton tallow, where stearin predominates. 
Stearin liquifies at 148°— Margarine at 118° and Elain remains 
fluid at zero of Fahrenheit. 

The adeps, though lodged in the cellular substance, is accommo- 
dated there under different circumstances from the cellular serosity. 
This doctrine was first promulgated by Dr. Win. Hunter,f and upon 
the following grounds : That certain parts of the cellular membrane 
are destitute of it; that in persons who have died from dropsy, the 
portions of the cellular membrane which originally contained fat, 
have a more ligamentous condition than others ; to wit, those on the 
loins next to the skin, more than the stratum next to the lumbar 
fascia ; that water or fluids pass readily from a higher to a lower 
part of the cellular membrane, either when extravasated naturally or 
injected ; that oil, when injected artificially, subsides in the same 
way, and has a doughy or (edematous feel, yielding readily to pres- 
sure and pitting, whereas, fat never shifts its position simply from 
gravitation. 

From these several causes, Dr. Hunter adopted the opinion that 
the fat of the cellular membrane is lodged in peculiar vesicles, and 
not as the water of anasarca, in the reticular interstices of parts. 
This idea has been adopted by Beclard, who says that the lobules 
of fat, when examined with a microscope, are seen to be composed 
of small grains or vesicles, from the six hundredth to the eight 
hundredth part of an inch in diameter, each one having a pedicle 
furnished from the adjacent blood vessel. That the parietes of the 
vesicles are so fine as to escape observation, but that he considers 

* Annales de Chimie, vol. xciv. 

j- Medical Observations and Inquiries. London, 1762. 



358 



INTEGUMENTS. 



them as arranged in the same way with the pulp of oranges, lemons, 
and such kind of fruit. 

The preceding observations on the probable existence of distinct 
vesicles for the reception of fat, are now proved by the microscope.* 
These vesicles are far from uniformity in size. A very common dia- 
meter is the sfo of an inch, but they vary from the i^Vi to the ^ ff . 
These vesicles are composed of organic, independent cells, which 
have the faculty of eliminating from the blood, the adeps, precisely 
upon the same principle that the organic cells of a gland, as the 
liver and mamma, eliminate bile or milk. The fat cells, are some- 
times dispersed at wide intervals in the cellular or areolar tissue, but, 
in other points, they are aggregated in masses, having a common 
envelope of laminated cellular substance. The interstices of such 
groups, are permeated by blood vessels, making a minute network, 
for the purpose of furnishing the proper elements to the cells. In 
particular parts of the body, as upon the soles and palms, but also 
elsewhere, the cellular substance is traversed by bands and filaments 
of fibrous matter for the purpose of holding them in place, and also 
of securing the skin from being torn off or dislodged. The ends of 
the fingers and toes exhibit striking arrangements of that kind. 



Fig. 5. 



Fig. 6. 



'<-%.% 




Areolar and Adipose tissue; 
a. a, fat-cells; b, b, filaments 
of areolar tissue. 



Capillary net-work surrounding 
the Fat-cells. 



Persons who are enormously fat, have in the composition of the 
latter a much higher proportion of Stearin, hence, in their dissection 
the hands of the operator, especially in warm weather are kept 



* Gerber's Elements of General Anatomy, p. 133. London, 1842. 



ADEPS. 359 

streaming with the oil. This portion of their fat, too, is disposed to 
gravitate to the lowest point during life, hence the ankles are tumid. 

Fat is more abundant in the female than in the male, and in both 
sexes it is removed as life declines. In the infant the fat is found 
at the surface of the body chiefly, little or none existing in the in- 
terstices of muscles, and in the cavities. 

Its uses are not fully understood. At some points it serves to 
diminish pressure, as on the hands and feet; at others it fills up in- 
terstices ; it is also a bad conductor of caloric, and may, therefore, 
serve in retaining animal heat. But its most general application is 
to the purposes of nutrition, it being one of those forms which nutri- 
tive matter assumes previously to being perfectly assimilated. This 
is very fully manifested in hibernating animals, which being fat in 
the beginning of their torpid state, return from it quite lean ; and in 
insects which during their repose in the chrysalis form, live upon 
their own fat while undergoing the metamorphosis into the perfect 
animal.* 

* Beclard, Anat. Gen. p. 170. 



PART II. 



OF THE DERMOID COVERING. 



The Dermoid Covering, or Tissue of the body, consists in the 
Skin; — its Sebaceous and Perspiratory organs; — the Nails; — and 
the Hair. 



CHAPTER I. 

Of the Skin. 

The Skin (Pellis, Cutis, hp/*.*) is extended over the whole sur- 
face of the body, and thereby constitutes a complete investment of 
it. At the orifices of the several canals which lead into the interior 
of the body, as the mouth, nose, vagina, anus, and urethra, it does 
not cease abruptly, but is gradually converted into the mucous 
membrane of the part, so that it is plainly continuous with it. At 
certain places, on the middle line of the body, the junction of the 
skin of the two sides is indicated by a change in its appearance, 
called Raphe ; as on the upper lip ; from the navel to the pubes ; on 
the scrotum, and in the perineum; in all of which places, in the 
development of the foetus, the two sides of the body are later in 
uniting than elsewhere. 

The colour of the skin varies in different nations: it is black in 
the Negro; of a copper colour in the American Indian; bronzed, 
or tawny, in the Arabian ; and white in Europeans and their de- 
scendants. It is also subject to various shades, from the mixture of 
these races, and from the influence of climate; its general tendency 
being to turn dark on parts exposed to the influence of tropical heat 
and light. 



CUTIS VERA, 361 

The external surface of the skin, or that which is free, has on 
it a great multitude of wrinkles ; some of them depend upon the 
subjacent muscles, as on the forehead and face; some are caused 
by the flexions of the articulations, and are to be seen at all of these 
places on the limbs; in addition to which, where there is much 
emaciation of the parts beneath, the skin not having sufficient 
elasticity to accommodate itself to their state, is thrown into other 
wrinkles, and sometimes into loose folds. Finer wrinkles of another 
description are also found on the skin, arranged in various angular 
and spiral directions: they depend on an entirely different cause, 
which will be treated of elsewhere. 

The skin abounds in hairs, which vary in fineness and in length 
according to the region over which they are distributed : it, like- 
wise, presents many small pits, or follicles, which are the orifices 
of sebaceous glands. A finer description of pores, which are visible 
only to the assisted eye, are supposed to be the orifices of exhalants 
and of-absorbents, but this is not so certain. 

The internal surface of the skin is connected to subjacent 
parts by the cellular tissue, which permits a considerable sliding of 
it backwards and forwards on most parts of the body. On other 
parts, however, this is restrained, as'on the cranium, the palms of the 
hands, and the soles of the feet, by ligamentous fibres passing to it 
from the fasciae and bones below. A very interesting attachment 
of this kind exists on the fingers, where a plane of ligamentous 
fibres is seen going from each side of the lower end of the first 
phalanx, downwards, to be inserted into the skin, half an inch or 
an inch off'; and the bulbous ends of the fingers thumbs and toes, 
exhibit also numerous fine ligamentous filaments of the same descrip- 
tion, passing amidst the granules of fat from the last phalanges. 

Since the first observation of Malpighi, on the tongue of a bullock, 
whereby he ascertained that its integuments consisted in three 
layers; and the discovery of a similar arrangement on other portions 
of the integuments by Ruysch ;* anatomists have, for the most part, 
admitted the skin to consist of three.laminse, the Cutis Vera, the Rete 
Mucosum, and the Cuticula. The latter two, however, have been 
recently identified, according to the opinion of Albinus at a former 
period, owing to their common origin as an epidermoid layer. 

* Thesaurus Anat. IX* 
Vol. L— 31 



362 



INTEGUMENTS. 



SECT. I. — OF THE CUTIS VERA.* 

The True Skin (Cutis vera, Derma, Corion,) is the deepest, or the 
layer next to the cellular substance. Its thickness varies according 
to age, sex, and the region of the body over which it is stretched ; 
on the trunk it is thicker behind than it is in front ; on the limbs, 
thicker on their external than on their internal faces or semi-circum- 
ferences. On the mammae, the penis, scrotum, and external ear, 
its tenuity is remarkable. When uninjected, it is perfectly white 
in people of all complexions, and in the living state has a semi- 
transparency that permits the blood to . be seen in the vessels 
beneath it. 

The internal surface of the true skin is so blended with the cel- 
lular substance, that in the recent subject there is a difficulty in dis- 
tinguishing where one terminates and the other begins, yet they may 
be separated by maceration so as^to determine this limit ; mortifica- 
tion of the cellular substance sometimes does the same thing; and 
in the ham, cured by salting and smoking, the true skin, after boil- 
ing, may be stripped off with but little difficulty. In either of these 
cases the internal surface of the latter is seen to be studded with, 
small areolar depressions, caused by the projection of granular 
masses of adeps ; the margins of these alveoli are the principal points 
of adhesion to the subcutaneous cellular tissue, while their bottoms 
are pierced with small openings that lead through the skin.f 

The external surface of the true skin is covered with very fine 
Papillae, or villi,! {PapillcB Tactus,) that are readily brought within 
the observation of the naked eye, by maceration, when protracted 
long enough to permit the removal of the cuticle. They consti- 
tute the Neurothelic Apparatus of Breschet. The projections on 
the tongue are very similar to them, and the whole are designated 

* Anat. Atlas, Figs. 136, 137. 

f Anat. Atlas, Fig. 141. £ lb. Figs. 139, 140s 



CUTIS VERA. 



363 



as the papillary body. These cutaneous papillae are particularly 
distinct at the bulbous ends of the fingers and toes, upon the palms 
and soles, on the lips, on the glans penis, and the nipple ; in other 
parts they are not so evident, but still there can be no doubt of their 
existence, from analogy. On the hands and feet they are arranged 
in double rows or files, which occasion the semicircular and spiral 
turns of .small wrinkles or ridges at the ends of the fingers and toes ; 
and the transverse, oblique, and curved ones, on other parts of the 
soles and palms. The small, triangular, lozenge-shape, and mul- 
tangular elevations of the cutis vera, seen elsewhere on its external 
surface, are caused rather by its contraction than by the papillae. 

These papillary projections resemble very much conoidal, cotton- 
like filaments, standing up from the twelfth to the third of a line, or 
thereabouts, from the surface of the skin: they are by no means so 
long as the villi generally of the intestines, and, like them, consist 
in very delicate ramifications of nerves and blood vessels, united 
by cellular tissue. In places where these papillae are less abundant, 
the cutis vera is not so vascular or sensitive. They readily receive 
a fine injection, and, if the cuticle be afterwards separated by ma- 
ceration, their vascularity is very distinct, as well as a tufted surface 
from subordinate projections from them, especially in the feet. 
Their nerves are destitute of neurileme.* The nerves and the blood 
vessels, end in terminal loops. The structure of the papillae has 
been especially studied by Pappenheim. 



Fi2. 7. 




Distribution of the nerves of the papillae at the extremity of the human 
thumb, as seen in a thin perpendicular section of the skin. 



* Beclard, Anat Gen. 



364 



INTEGUMENTS. 



Piar. 8. 




Distribution of Capillaries 
in the papillae of the skin of 
the fingers. 



The texture of the true skin is filamentous ; the fibres which com- 
pose it, by their irregular intermixture, resolve it into a sheet of net- 
work or areolae, the meshes of which are 
sufficiently large in some parts to permit 
the introduction of the head of a small 
pin. The meshes, though they are 
larger and more distinct on the internal 
than on the external surface of the true 
skin, open, however, upon the latter 
surface ; having passed through the skin 
obliquely, after the manner of the ureters 
through the coats of the bladder. Those 
intervals between the fibres of the skin 
are rendered very obvious after macera- 
tion of a month or two, or after skin has been tanned. They serve 
to transmit hairs, blood vessels, nerves, absorbents, and exhalant 
vessels also if such exist. These interstices communicate freely with 
the cellular substance, for in many cases of anasarca, blisters, when 
made upon a depending part, empty the cellular membrane of water 
almost as quickly as scarifications ;* but if the blisters inflame, they 
discharge inconsiderably, owing to the porosities being shut up by 
lymph and by the tumefaction and fullness of the parts. The same 
is observable in scarifications. 

The precise nature of the tissue which composes the true skin 
is not yet fully ascertained ; it seems, however, to be a mixture of 
cellular substance and ligamentous matter; with a striking predomi- 
nance of the latter in most parts of the body, though its proportion 
varies considerably, being very abundant on the thickest parts of 
the skin, while it is scarcely discernible on the thinnest. The fol- 
lowing analogies of dermoid with ligamentous or desmoid tissue are 
observable. It becomes yellow and transparent on being boiled, 
and a continuation of the process dissolves it into gelatin. It re- 
sists putrefaction for a long time ; is remarkably tenacious. Con- 
trary, however, to ligamentous matter, it is extensible and elastic, 
though this property may arise from the oblique intertexture of its 
fibres ; as a bandage from a piece of muslin, when torn longitudinally 
or transversely, is inelastic, but if it be cut bias, is then very elastic. 



* W. Hunter, loc. cit. 



RETE MUCOSUM. 365 

The application of tannin increases its resistance, and makes it one 
of the strongest animal substances known in human arts. 

The cutis vera is very vascular, and abounds also in nerves and 
absorbents. The demonstration of the latter, on its outer surface, 
has been accomplished by Tiedeman, Lauth, and Fohman, 

The skin has a very strong power of contraction, which is mani- 
fested in an amputation, in a long incised wound, or when a sensa- 
tion of chilliness exists, as in an ague or from the application of cold. 
Owing to the diminution in size of its areolse, its external surface 
then becomes wrinkled, rough, and studded w T ith projecting points, 
constituting the Cutis Anserina. 



SECT. II. — OF THE RETE MUCOSUM.* 

The Mucous Net or Rete Mucosum,f of Malpighi, is the inner 
surface of the Epidermoid layer of the skin, and is that in which 
resides the colour of the several races of men. It covers every part 
of the surface of the cutis vera ; its existence, however, is not so ob- 
vious beneath the nails and about the junction of the skin with mu- 
cous membranes, as it is elsewhere ; though taking all things into 
consideration, it is probable that it exists also at these several places, 
but much finer. It is so extremely thin, and of such a soft mucila- 
ginous consistence, that it is difficult to separate it as a distinct la- 
mina, either by maceration or by any other means ; for it most com- 
monly peels off by adhering to the cuticle, after the manner of a 
pigment. It, however, by good management, may be fairly raise d 
as a membrane, and separated for a certain distance from the other 
two coats of the skin. 

Fine as this membrane is, it would seem, from the observations of 
Mr. CruikshankJ upon a negro dead from small-pox, and upon a 
preparation executed in London, by the late Dr. Baynham, of Vir- 
ginia^ and from more recent experiments in Paris, by M. Gaultier,|| 

* Anat. Atlas, Fig. 138. 

f Caldani, Icon. Anat. PI. xci. Albinus, Annot. Acad. Leyden, 1756* 
Ruysch, Thes. Anat. ix. 

$ Expts. on Perspiration. London, 1795. 

§ Wistar's Anat. vol. i. p. 39-1. 

|| Recherches sur la peau, Paris, 1809 ; in Anat. De L'Homme, par J. dp-. 
<juet. PI. cxvn. 

31* 



366 



INTEGUMENTS. 



that it consists in several layers. 1. Upon the inequalities or pa- 
pillae of the cutis vera, there is a layer called, by M. Gaultier, 
bloody pimples, (Bourgeons Sanguins,) but which, in the opinion of 
some other anatomists, are only the papillae themselves of the cutis 
vera. 2. Then there is a very thin and transparent coat, called 
from its colour, Tunica Albida Profunda : it is especially visible in 
the negro ; under the coloured horns and scales of animals, and be- 
neath the nails of white persons. 3. Over this layer is spread another, 
(the Gemmula,) which contains the colouring matter of the several 
complexions of the human family, and consists in a multitude of 
dark brow T n points or granules in the negro ; it is visible also in 
those forms of disease called ephelides (freckles,) by the French, 
where the skin becomes spotted ; it is not so distinct in the healthy 
state of the white individual. 4. The last lamina of rete mucosum, 
is called, by M. Gaultier, Tunica Albida Superficialis, from its 
whiteness and superficial situation ; in many animals it is very dis- 
tinct, in the negro somewhat so, but in the white it is not to be seen 
except under the nails, about the hair, and under accidental horny 
excresences. 

These observations of M. Gaultier have been verified by M. Du- 
trochet,* in experiments upon the texture of the skin of verte- 
brated animals ; and were generally acknowledged by the French 
anatomists. In negroes, in cutting through the skin of the sole of 
the foot, from heel to toe perpendicularly to the furrows, this ar- 
rangement is readily recognised ;f and when it has become indis- 
tinct, it may be improved by immersing the skin for three or four 
days in lime-water, or a solution of potash or barytes, and after- 
wards keeping it the same length of time in a solution of corrosive 
sublimate. Blisters also elucidate this point on other parts of the 
body : the fluids being locally attracted there, infiltrate the rete mu- 
cosum, and separate in part its layers, so as to form a vesicle fre- 
quently very thick, particularly in fat persons. 

The rete mucosum is very readily affected by the Salt antiseptic 
mixture,! so that it becomes dissolved, and thereby allows the cu- 
ticle to loosen from the cutis vera. This fact repeatedly noticed in 
the use of the injection and for years, I attributed for a long time to 

* Journal de Physique, May, 1819. Journal Complementaire, vol. v. 
f J. Cloquet, Anat. De L'Homme. PI. cxvi. Fig. 6. 
t Amer. Jour, of Med. Science. Jan. 1845, p. 245. 



RETE MUCOSUM. 367 

putrefaction, through mistaken views of its real character. I am 
now satisfied that it is the result of the solvent power of the alkali 
in this injection: and, as the latter acts so decidedly on the central 
masses of the nervous system in softening them, probably from the 
adipose matter contained in them, it is hence, not illogical to con- 
clude that the rete mucosum itself has a large proportion of neurine, 
in its composition, which idea is in harmony with the sensibility of 
the external surface of the cutis vera. This injection has a similar 
softening influence on all mucous membranes, making them almost 
liquescent. 

The scrotum of the negro is also well suited to the exhibition of 
the rete mucosum, as it is there very distinct, and is universally 
much thicker and better marked in the negro than in any other 
race. From its extreme tenuity in the whites its existence in them 
has by some persons been doubted, but erroneously, as in them also 
its change of colour, from the influence of the sun, is readily demon- 
strated. There are in fact few persons, perhaps none, so white, 
but what a slight tinge of yellow exists in their skins; which may 
be proved by contrasting them with any perfectly white surface, as 
snow, bleached paper, or linen. This slight tinge of yellow is in- 
creased to an olive colour by the sun's rays, and, in some instances 
by a spontaneous deposite ; in other cases, it is in certain spots re- 
moved, so as to leave a colour almost perfectly white, or that only 
of the cutis vera.* When the latter change occurs in the African, 
it occasions a hideous piebald complexion, and the cuticle is readily 
elevated into blisters, by the irritation of the solar rays. Some 
persons have an entire deficiency of this pigment on the skin, from 
birth ; the same deficiency occurs in the eyes, and hair ; they are 
designated as albinos. The deficiency of the pigmentum nigrum 
in the eye, causes it to look red, like that of the white rabbit; and 
also makes it intolerant of a strong light, as that of noon-day. 

The pigment of the rete mucosum would seem, for the foregoing 
reasons, to be continually undergoing a deposition and absorption. 
When it has been lost by a blister in an African, it is generally 
restored in a short time afterwards: the same occurs in their cica- 
trices, but requires a longer period. The observations of chemists 
tend to prove that it is formed principally by carbon. Its apparent 

* A case of this kind is now in the Philadelphia Alms House, where the 
absorption of colour has occurred in spots on the hands of a dark-complexioned; 
European. June 15, 182C. 



36S INTEGUMENTS. 

use is to defend the skin from the rays of the sun, in illustration of 
which several ingenious experiments have been executed by Sir 
Everard Home.* 

The influence of the continued use of nitrate of silver, in giving 
a lead colour to the skin is well known. 

Anatomists generally have rejected the idea of the essential vas- 
cularity of the rete mucosum, yet it would seem to have been in- 
jected, on one occasion at least, by the late Dr. Baynham, in a leg 
which was diseased from exostosis;! and there are now in the ana- 
tomical cabinet of the University, three preparations by myself of 
the fingers of an African, where the colouring matter of the injection 
has been passed from the papillse of the cutis vera into the rete rau- 
cosum ; and there deposited in dots, indicating the former position 
of the papillse. 

The Rete Mucosum is considered by some as a freshly secreted 
layer, from the cutis vera, which, finally, becomes cuticle by its. 
passing outward and becoming condensed and dried.:}: The obser- 
vations of Henle go to show that it is constructed of minute oval cells, 
having each a central nucleus, and as they advance to the surface so 
as to become cuticle, they change their form into flattened scales. 

Messrs. Breschet and Vauzeme§ also limit the number of cutaneous 
layers to two, the cutis vera, and what they call the corneous tissue 
or epidermic layers, which mean the rete mucosum and the cuticle 
of anatomists generally. These two, they say, are a secretion of 
an apparatus in the thickness of the skin, and which they call 
blennogenous from its product, a mucus, which finally inspissates 
so as to form the rete mucosum and the cuticle. This apparatus or 
parenchyma, is furnished with short secretory canals which deposite 
the mucus between the bases of the papilla? tactus. 

There is also, they assert, a glandular apparatus which they call 
chromatogenous, and furnished with ducts, it being likewise in the 
thickness of the cutis vera and discharging on its surface. The office 
of it is to secrete the coloured matter of the rete mucosum, hence its 

* Philos. Transact., London, 1821. 

f Meckel speaks familiarly of its being furnished with an innumerable 
quantity of capillary vessels. Vol. i. p. 470. 

£ Miiller — Carpenter, &c, 

§ Nouvelles Recherches sur la structure de la peau par G. H. Breschet et 
Koussel de Vauzeme. Paris, 1835. 



RETE MUCOSUM. 369 

name. But its function is also the secretion of the more solid parts 
of the corneous layer, as the epidermis with its extensions in the 
form of scales, horns, spines, nails, hoofs, hair, wool, &c. 

Mr. Breschet, in addition, alledges the existence of a distinct 
inhaling apparatus in the rete mucosum commencing immediately 
under the superficies of the cuticle and collecting its branches to 
terminate in the lymphatics of the skin: he does not claim to have 
seen their mouths. 

The tendency of microscopical anatomy, at the present day, it is 
thus seen, is to indentify the rete mucosum with the cuticle, by view- 
ing it as the first development of the cuticle. It is there in the form of 
nuclei, in various stages of growth into cells, and held together by a 
tenacious semi-fluid substance. More exteriorly, these cells are nearly 
spherical, farther on they become, by reciprocal pressure, polygonal, 
and then flattened as they pass out to form the real cuticle. The 
colour of the rete mucosum, is produced by a quantity of what are 
called Pigment cells, intermixed with the others, and which make 
the same transition from the cutis vera to the surface. They are 
seen with difficulty in the white subject, but easily in the coloured 
races : but the choroid coat of the eye in all races, exhibits them 

most freely and beautifully. They each have a nu- 

... Fio\ 9. 

cleus, and present an accumulation within, of nume- 
rous rounded or oval granules, measuring the ^,W of 
an inch in diameter. What is remarkable about these 
granules, is, that they, when examined separately, 
are found to be transparent, and not black and 
opaque — and also exhibit an active movement. This Pigment 
black pigment contains nearly sixty per cent of Car- ce ^ s ma £ n i- 

bon.* Light would seem to be the active cause of e '' la " 
,..,.,.. , , . meters; — a, 

this pigment, which is introduced as a protection to 11.7, 

the delicate cutis vera, in the different races of human cleus. 
beings, in a proportion harmonizing closely with their 
locality on the surface of the earth, and with the delicacy of tex- 
ture of the cutis vera itself. 

If the distinction heretofore admitted, between the Rete Mucosum 
and the Cuticle, is to be abolished from the influence of microsco- 
pical observation, then of course, the expositions of Gaultier and of 
Dutrochet, above recited, are to be qualified also. But, at the same 

* Carpenter, Elem. of Physiol, p. 147. 




370 



IXTEGOIEXTS. 



time, much difficulty will arise to the practical anatomist in account- 
ing for the succession of distinct laminae of the rete mucosum, exhi- 
bited sometimes by blistering, and in preparations, of which we 
hare some in the Anatomical Museum, where the delimitation of 
layers, is as well marked between the rete mucosum and cuticle, as 
between a coat sleeve and its lining. Another suggestion may also 
be made, which is, that as the rete mucosum is the basement layer 
at any rate, so its name ought to be retained, and that of cuticle 
suppressed. 

It appears to me, plainly, that the division into rete mucosum and 
into cuticle, with the admission that the latter is derived from the 
rete mucosum, (an opinion of considerable date) is at any rate al- 
most indispensable to clearness in arranging the facts, connected 
with the two : unquestionably there are at present, many existing 
anatomical divisions upon lighter grounds. 

In some very remarkable instances the skin becomes suddenly 
black. " We have read to the Society of Medicine of the Faculty, 
the history of a woman whose skin became black in the period of 
a night, in consequence of a strong moral impression. This woman 
had seen her daughter throw herself out of the window with her 
two little children ; and we have since had occasion to see, also, a 
woman, who having escaped capital punishment, in the revolution, 
had experienced the same accident. The latter was at the period 
of menstruation when she learned this news. The menses were 
immediately suppressed, and from white, which she was, she became 
black as a negress, which colour continued even to her death. We 
dissected with care the skin of these two women, and found the 
coloured portion to be the rete mucosum. We found it sufficiently 
easy to isolate the epidermis and the dermis, which presented no 
abnormal coloration. This black colour must be the result of a 
sanguineous exhalation which operates upon the rete mucosum." 

" The violet tinge of the skin is, ordinarily, the result of embar- 
rassed circulation. The skin becomes blue in many very advanced 
diseases of the heart. The name of Cyanosis, or blue disease, has 
been given to this colour of the skin, which is falsely attributed to 
an immediate communication of the auricles by means of the un- 
obliterated foramen ovale. This cause of the cyanosis is much more 
rare than is commonly supposed."* 

* Cours de Medecine Clinique, par Leon Rostan. Paris,1830. 



CUTICLE. 371 



SECT. III. — OF THE CUTICLE (CUTICULA.)* 

The Cuticle or Epidermis, is the most superficial portion of the 
dermoid covering, and takes its wrinkles from the closeness of its 
application to the true skin. It is a thin, dry pellicle, which cannot 
be separated from the cutis by dissection ; in consequence of which 
we have to resort to the alternate application of hot and cold water ; 
to partial putrefaction ; or in the living body to vesicatories. The 
adhesion between the cuticle and the true skin is through the inter- 
vention of the rete mucosum, which being the matrix of the cuticle, 
and making a uniform adhesion to the cutis vera, establishes of course 
the same uniformity for the cuticle itself, which, as just stated, is 
a modified free surface to the rete mucosum. 

In most parts of the body the cuticle or the outer face of the Epi- 
dermoid layer presents itself of a thickness uniformly about that of the 
thinnest Chinese blotting paper. Upon the palms and soles of per- 
sons generally, but especially of such as are addicted to heavy labour, 
and exposed to a continued mechanical irritation of these parts, the 
cuticle becomes much thickened and laminated, obviously from a 
successive deposite of it on the cutis vera. It is transparent, by 
which the colour of the parts beneath is readily discernible ; in the 
African, however, it is extremely difficult, nay, impossible to clean 
it wholly of the colouring matter of the rete mucosum. 

The structure of this body is as follows ; there is no evidence 
whatever of the existence of vessels in it : on the contrary, in in- 
flammations, when the skin becomes of the deepest tinge of red, the 
epidermis never has its colour changed in the smallest degree ; the 
impression made on it is only manifested by its dropping off, while 
another layer is preparing to take its place. 

A fine injection, when forcibly driven into the extremities of a 
foetus, will become extravasated between the cutis vera and cuticle 
and raise up the latter in small blisters, as I have frequently expe- 
rienced, though it cannot be caused to pass through the cuticle. 

Dr. W. Hunter, though he disbelieved in the possibility of inject- 
ing the cuticle, and did not admit the evidence of the preparations 
of his time having that reputation ; yet thought the communicating 
or perspiratory vessels might be exhibited in a different manner, that 
is, by macerating for a short time a piece of the sole of the foot : 

* Anat. Atlas, Fig. 135. 



372 



INTEGUMENTS. 



afterwards, in separating the cuticle from the cutis vera, as the two 
membranes parted, these vessels would be found in the angle of se- 
paration passing from one to the other like cobweb filaments.* 

There can be no doubt of this appearance, for it is easily verified 
by any one who will take the trouble to perform the experiment. M. 
Beclard has suggested, that these filaments are merely the threads 
formed out of the rete mucosum, which is rendered a viscous fluid 
by the commencement of putrefaction ; and, therefore, when parted, 
will put on the same filamentous appearance that half dissolved 
glue does in a similar situation. Some of the aforesaid filaments 
also are supposed by Bichat and Chaussier to be absorbents. 

Neither nerves nor cellular membrane exist in this tissue ; thus it 
is in all states entirely devoid of sensibility, and never puts forth 
granulations. The excrescences which belong to it, as corns and 
indurations, are, like it, laminated, owing to their thickness, and 
have no interior circulation ; and though sometimes painful, are so 
only by their pressing upon the subjacent nerves of the skin. It is 
also destitute of filaments. 

The cuticle is penetrated by hairs, and by the orifices of the su- 
doriferous and sebaceous follicles and glands; and according to 
Bichat, also, by the exhalants and absorbents, the several orifices 
of which, he says, become distinct by holding it between the eye 
and a strong light. As it, when raised by a blister, does not allow 
the effused fluid to pass through any of these pores, it is very rea- 
sonably supposed that they are all oblique, and, therefore, exercise 
a valvular office on such an occasion. Or if, according to the ori- 
ginal supposition of Mr. Cruikshank, now sufficiently verified by the 
microscope, the finest pores of the cutis vera are lined by processes 
from the cuticle, the collapse of these processes on the separation of 
the cuticle will also account for the fact. It seems to be well ascer- 
tained at the present time, that as the epidermis is more transparent 
at certain points than elsewhere, the appearance has been mistaken 
for porosities of exhalants and absorbents. The cuticle, w r hen de- 
tached, will not allow a column of mercury to pass through it, ex- 
cept its weight be so great as to lacerate it : this fact is rather against 
the doctrine of pores being visible when examined by permitting the 
light to shine through, and shows that even those for the hairs and 
the sebaceous follicles are stopped by some arrangement or other. 

* Med. Obs. and Inquiries, vol. ii. p. 53, London, 1762. 



cuticle. 373 

The cuticle has but little power of extension, and, consequently, 
of contraction, and tears with the application of a very slight force. 
It naturally contains so little moisture, that its bulk is only incon- 
siderably altered by drying. It, like the hair or nails, resists putre- 
faction so much, that it has been found in burial places after a lapse 
of fifty years. When held in water, it swells, becomes white, 
wrinkles more, loses its transparency, and dulls the sensibility of 
the cutaneous papillae. It cannot, like the true skin, be readily 
reduced by boiling water, into gelatin, and, consequently, is not 
affected by tanning : it, indeed, retards that process, when left on 
the proximate surface of the cutis vera. When applied to a fire, 
it burns like the hair and nails, with extreme facility, owing to the 
presence of a similar oil in it, and it gives out a very disagreeable 
odour. 

The little extensibility of the cuticle causes it to be ruptured 
whenever tumours, as warts, &c, rise from the surface of the cutis 
vera: it is supposed, however, not to be entirely deprived of this 
quality, as it seems to stretch when raised into a blister, though this 
may come, in some measure, from the small wrinkles naturally ex- 
isting in it being drawn out. It has not the slightest sensibility, 
neither is this quality evolved by any condition whatever, as it is 
in tendons, ligaments, and bones, when they become inflamed. 

The cuticle consists of several successive layers of compressed 
cells, originally derived, as stated, from the cutis vera by the inter- 
mediate transition into rete mucosum. These cells finally be- 
coming scales of more and more density as they are nearer the super- 
ficies, are continually lost by desquamation and supplied by a new 
secretion advancing through all the intermediate gradations. Ori- 
ginally of a spherical shape they become more and more compressed, 
until they are finally flat planes, or nearly so, with no trace of a 
central nucleus. The epidermis is absolutely uninterrupted on the 
surface of the body, so that it is visibly extended even over the 
cornea where it presents one of the best examples for the microscope, 
of the scaly arrangement. 

From the epidermis having in itself no power of regeneration, owing 
to its deficient organization, the most plausible opinion in regard to its 
source is the above; As the external layer of the rete mucosum, it 
undergoes there an inspissation, and some modification which render 
it a sort of varnish, well qualified to resist the agency of exterior 

Vol. I.— 32 



374 



INTEGUMENTS. 



objects, and to protect the delicate organization of the proximate 
surface of the cutis vera. This opinion of its origin seems to be 
adequately proved by its participating in the colour of the rete mu- 
cosum, more or less, so as to give it a sensible tinge, which cannot 
be washed from it. 



Fiff. 10. 



Fier. 11. 




Oblique section of 
Epidermis, to show the 
successive development 
of its component cells ; 
— a, nuclei, upon the 
outer surface of the cutis 
vera/,- the nuclei are 
found to be gradually de- 
veloped into cells, at b, 
c, and d ; and the cells 
being flattened into la- 
mellae, form the exterior 
portion of the epidermis 
at e. 




Scales detached from 
the epithelium of the 
tongue, magnified three 
hundred diameters. a, 
scale — b, nucleus— c, glo- 
bule of fat attached by ac- 
cident. 



Fig. 12. 

*':>>#;> 

©«©«-• 

Mo' 1 */ 
9 » ^ © 

Molecules of pigment, 
magnified, 500 diameters. 



That a loss and reproduction of the cuticle is constantly going 
on is manifested by the large quantity of branny scales that are de- 
tached from its surface, when one has abstained from bathing for a 
long time. This is more remarkable on the palms and soles than 
elsewhere, and the loss must of course, be continually supplied. It, 
as is well known, is rapidly regenerated when it has been lost sim- 
ply by an abrasion or blistering, which has not interfered with the 
organization of the rete mucosum. In some cases there is an unu- 
sual development of it : Bichat retained the skin of a patient, dead 
at the Hotel Dieu, in whom the cuticle, at the period of birth and in 



CUTICLE. 375 

subsequent life, was three times the natural thickness ; and had 
always, with the exception of that of the face, been subject to a con- 
tinual desquamation. 

One of the most striking properties of the cuticle is its resistance 
to evaporation from the surface of the body: in a subject, any part 
of the derm, when deprived of it and exposed to the air, dries up 
in the course of a day or two ; while the other portions remain soft 
and flexible for weeks, and, if it were not for putrefaction causing 
the cuticle to peel off', would sometimes remain so for months. 
Though it suppresses evaporation, in a great measure, it does not 
do so entirely; for, after a subject has been kept some time, its 
fingers, toes, nose, and ears get very dry and hard. 

The power of the cuticle to absorb or to transmit inwardly articles 
through it, is not by any means so obvious as its exhalation: th e 
facts, however, upon the whole, seem to prove that though this 
power is much curtailed when compared with that possessed by 
mucous surfaces, yet it does exist to a certain extent.* 



CHAPTER II. 

Of tlie Sebaceous, Perspiratory and Odoriferous Organs of the Skin. 

The Sebaceous Organs consist in Follicles ( Cryptce Mucosa) and 
Glands, ( Glandulce Sebacece.) 

The Sebaceous Follicles, probably according to the suggestion of 
M. Beclard, exist over the whole surface of the skin, with the excep- 
tion of the palms and soles; because the skin is universally rendered 
unctuous by a discharge : because many follicles exist, which are 
only visible to the microscope ; and because morbid changes fre- 
quently render them evident, where their existence was not sus- 
pected before. In many places these follicles are sufficiently obvious 
and very numerous, as on the nose, about the corners of the mouth, 
on the ear and behind it, and on the entire face, of some individuals. 
They consist of small pouches like inflections of the surface of the 

* Wistar's Ajiat. Vol. ii. p. 396, 3d edit. 



376 



INTEGUMENTS. 



skin placed in its thickness, and when it has been injected, are 
seen to have their parietes abundantly furnished with blood vessels. 
The discharge from them sometimes becomes inspissated, and 
does not readily pass through their orifices ; in which case, con- 
tinuing to accumulate, it will, finally, form a sensible tumour, 
Most frequently it does not collect to such an extent, but is indi- 
cated simply by a small black point, owing to the adhesion of dirt 
to it : in this condition, when squeezed out, it assumes a small 
vermicular shape. 

The sebaceous follicles are said by Mr. Erasmus Wilson to be the 
residence in great numbers of a curious parasite, the Demodex Fol- 
liculorum. The inhabitants of large towns are especially the sub- 
jects of this condition.* 

The Sebaceous Glands, properly speaking, are about the size of 
a millet seed, of a light yellow colour, and are placed, wherever 
they exist, immediately under or near the cutis vera. They are 
particularly numerous under the skin of the mons veneris. The 
latter glands may, however, possibly, belong to the same order 
with the miliary glands just under the skin of the axilla. ; and pre- 
sently to be noticed. 

The sebaceous glands are a more complex arrangement of the 
simple follicular excavations, and consist of groups of the latter re- 
sembling in shape a blackberry, each cell being distinct, but all dis- 
charging into a common duct. Sometimes they are laid down in 
the form of a long tube w r ith side cells or canals entering into it ; 
the Meibomian glands of the eyelids being of this description. 

Where the hair is abundant, as on the head, chin, mons veneris, 
&c, the ducts of the sebaceous glands discharge to a large extent 
into the sac containing the hair.f 

The sebaceous organs furnish the oily exhalation, which lu- 
bricates the surface of the skin, gives linen, when worn a long 
time, a greasy appearance, -and causes the water in which we 
bathe to assemble in drops, on the surface of the body, rather than 
to wet it uniformly. This humour produces a rancid disagreeable 
smell from the surface of such persons as do not resort to ablutions of 
the whole skin, from time to time. It is particularly abundant about 

* Carpenter's Elements of Physiol, p. 428. Phil. 1846. 
f Anat. Atlas, Figs. 142-3. 



THE SEBACEOUS ORGANS. 377 

the places provided with hairs, as the scalp, the genital organs, the 
axillce, and seems to be intended to maintain the flexibility and 
smoothness of the skin and hair, and to prevent the former from 
chapping. These qualities of it are possessed, in a considerable 
degree, by the oily articles of the toilet, which are used for the same 
purpose. There can be no doubt of the unctuous quality of this 
secretion, as, when collected on a piece of clothing or on blotting- 
paper, it burns with a white flame. Its quantity is readily augmented 
by certain kinds of clothing, which most persons must have observed 
shortly after putting on a flannel shirt next to the skin. 

It is sufficiently certain that the apparatus producing this oil is not 
visible to the naked eye in most parts of the skin, so that there 
would seem to be some necessity of accounting for its appearance 
there, either according to the suggestion of Mr. Beclard as above, 
or in some other way besides by evident glandular bodies. Bichat 
considered it to arise from a set of exhalants differing from those 
which secrete the matter of perspiration, a theory far more rational 
than that which attributes it to the percolation of the subcutaneous 
fatty matter. 

Tlie Perspiratory Organs. — The perspiration is the product of cer- 
tain bodies called the Sudoriparous glands, investigated particularly 
by Gurlt.* They are contained in the substance of the cutis vera, 
but project also into the subcutaneous cellular tissue. Like the se- 
baceous glands and follicles they are presumed to be inflections or 
processes lined by cuticle sometimes simply cylindrical or club- 
shaped, but in other instances collections of small sacs, resembling 
a mulberry or blackberry which have a common duct. Their ducts 
are either straight or spiral, and open upon the ridges of the epider- 
mis made by the papillae tactus. The orifice is said by M. Breschet 
to be oblique. 

The perspiratory glandsf are very small, almostjtransparent, and are 
found with most ease on the palms of the hands, and on the soles of 
the feet, according to Gurlt. 

During life the process of perspiration is continually going on, 
either in a sensible or insensible manner; and according to the ex- 
periments of Sanctorius, more than one-half of the weight of our 

* Anat. Atlas, Figs. 144, 145, 146, 
f Gerber, p. 143. 

32* 



378 INTEGUMENTS. 

food is lost in that way through the skin and lungs. MM. Lavoisier 
and Seguin ascertained that the proportionate exhalation from these 
organs was eleven of the former to two of the latter. When the 
perspiration is rapid, it assembles on the surface of the body in the 
form of small drops, having an acid, saltish taste, and a peculiar 
odour. In this state, according to the analysis of Berzelius, it 
consists principally in water, holding in solution a hydrochlorate ot 
soda and of potash, some lactic acid, lactate of soda, and a little 
animal matter. The perspiration, besides its use as an excretion, 
is a powerful means, by its evaporation, of enabling the body to 
resist a high temperature. It varies, both in quality and quantity, 
according to age, sex, state of health, food, and habits of life. 

The estimate of Krause is, that there are on an average one thou- 
sand orifices of sweat glands, over every one inch square of the 
surface of the human body. The largest numbers being on the 
sole and palm, and amounting to about twenty-seven hundred,— 
and the smallest on the neck, back, and nates, and exceeding 
somewhat four hundred. The entire number he fixes at 2,381,248*. 

The original sentiment of Dr. W*. Hunter on the perspiratory 
vessels, being in fact, the delicate filaments between the cuticle and 
cutis vera, seen on separating them, has been reproduced by Gurlt, 
who considers these filaments to be the ducts of his perspiratory 
glands. The arguments against their being the merely softened rete 
mucosum, as suggested by Mr. Beclard, are their very uniform size, 
one with another ; their spiral line of progress ; and their reappearance 
at the same spots exactly, which could scarcely be the case, in an 
inspissated fluid drawn out into strings, and then allowed to collect 
itself again into a mass, or layer. The process being repeated over 
and over again with these filaments, will show them constantly re- 
turning to the same condition. 

The Odoriferous Glands, (Glandules Odoriferce,) I have ventured 
to give this name to a layer of well marked subcutaneous glands 
placed in the axilla, and which have been too much neglected by 
anatomists, indeed there are many modern systems in which they 
are not even alluded to. They are remarkably well evolved and 
distinct in the negro, though not peculiar to that race, and are just 
beneath the skin of the arm pit, embedded in the common adipose 
cellular membrane, and intermixed with the bulbs of the hairs. 

It is well known in our country that the smell of negroes is par- 

* Muller's Archives, 1844. 



THE ODORIFEROUS GLANDS. 



379 



ticularly redolent from the axilla ; (the same may be said in a quali- 
fied way, of persons of all complexions ;) and that some of them, 
with the strongest efforts to free themselves from it, are so organized 
that they may be traced by the effluvium with which they impreg- 
nate the air. The layer of glands represented in the accompanying 
figure will, I think, go largely towards an explanation of that fact, 

Fiff. 13. 




and in doing so, they may not be improperly called the Odoriferous 
Glands of the Axilla. They belonged to an almost coal black male 
subject, of fine development of skeleton and muscle, not advanced 
in life, and which was used for the anatomical lectures.* The 
piece is represented as it stands suspended in a round bottle of some 
sixteen or eighteen ounces, and under a magnifying influence 
which enlarges the diameters about one-third. 

From the representation it will be seen that these glands amount 
to from two hundred and fifty to three hundred, and make a circular 
plate about the size of a large Spanish dollar. In raising the skin 
of the axilla, they are found very near it, and as the skin there is very 
thin, the principal thickness of the tegument is derived from the sub- 
cutaneous cellular layer. These glands are so invested and masked by 
the layer, that unless a special examination be made for them they are 

* December, 184<L 



380 INTEGUMENTS. 

almost certainly overlooked ; with the attention, however, directed 
to them they are found with unerring certainty ; and become still 
more conspicuous by a coloured injection and by maceration in 
water, which infiltrates the cellular substance. They are heaped up 
near the centre, become more and more scarce towards the circum- 
ference, and at the latter have distant intervals between them, some 
few being so scattered as to form the outposts of the circle. 

These glands are of a fuscous colour, and vary in size, some being 
only the half of a line or less in diameter, and others reaching to two 
lines. The central ones are the larger. They bear upon their sur- 
face the granular aspect so common to similar composite glands as 
the labial and buccal — the pancreatic and the mammary. Their 
magnitude is too great to suppose that they are a simple appendage 
of the hairs of the axilla, which indeed in this subject are few and 
small : neither do they admit entirely of being placed in the category 
of perspiratory glands. 

The largest sebaceous glands of the skin, as stated by Gerber,* 
considered now excellent authority, are the Meibomian glands as 
encountered on the eyelids. He also says with others,! that the se- 
baceous follicles of the skin "generally open laterally into the hair 
sheaths — they always occur isolated, and are not so universal as the 
more compound sebaceous glands." In regard to the perspiratory 
glands of Gurlt, the same authority says,:}: " that their contents being 
watery and uncoloured with pigmentary matter, they are highly 
transparent, and much more difficult to discover and to examine 
under the microscope than the sebaceous glands." 

The necessity or rather probability of a distinct glandular appa- 
ratus, for the peculiar effluvium of the human skin, has been hereto- 
fore frequently conjectured. Thus, besides others we have a recent 
distinguished authority advancing, that it is probable that by glands 
of special functions are elaborated the odorous secretions which are 
exuded from particular parts of the surface, especially the axilla. § 
The same idea is presented in the learned work on Physiology, by 
Prof. Dunglison, || in the ^declaration that the sebaceous follicular 
secretions differ materially according to the part of body where they 

* Elem. Gen. Anat., p. 142: London, 1842. f Id. p. 327. 

i Ibid, p. 144. 

§ Principles of Human Physiology, p. 584. By W. B. Carpenter : London, 
1842. 

|| P. 95, vol i., Philadelphia, 1844. 



THE ODORIFEROUS GLANDS. 381 

exist, as manifested by the varying fluids discharged in the axilla, 
groins, feet, &c. The real anatomical views of those gentlemen, 
however, as well as of Muller* and of other physiologists, do not 
seem to go beyond the admission of the ordinary sebaceous crypta?, 
and of the sebaceous glands in connexion with the hairs. 

These glands, though much neglected at the present day, were bet- 
ter known at a former period. The celebrated Winslow, Professor 
of Anatomy in the University of Paris, speaking of the Cutaneous 
Glands, commonly called Glandulse Miliares, says, that the under 
surface of the skin is covered by them, and that they are fixed in 
fossuloe common to the skin, and subcutaneous cellular substance, 
and that their excretory ducts open on the outer surface of the skin, 
sometimes on the papillse, at others on the side of them, as may be 
seen even without a microscope in the ends of the fingers. The 
greater part of them, he considers to furnish sweat, and others 
a fatty oily matter, as on the scalp, on the back, behind the ears, on 
the nose. He also asserts, that by macerating the skin in water, 
these miliary glands become more visible, especially in the skin of 
the lower part of the nose, and in that of the axilla. " The late Mr. 
Duvernay (the master of Winslow,) demonstrated to tLe Roytri 
Academy, that the structure of some of the cutaneous glands, re- 
sembles the circumvolutions of the small intestines plentifully stored 
with capillary vessels."! These observations may be considered as 
the precursors of the present state of the glandular Anatomy of the 
skin, as designated by the microscopical Anatomists, Gurlt, Gerber, 
Wagner, Tod and Bowman, and still more recently, by Mr. Ch. 
Rolin,| before the French Academy of Sciences, who has also ob- 
served them in the groin, where he considers them to be less abun- 
dant than in the axilla. But to Duvernay, as above, may be safely 
awarded the credit of elucidating the tortuous line of their ducts, as in 
the acknowledged course of the sweat glands by Gurlt, and of the 
ceruminous by Wagner. 

* Physiology, p. 481 : London, 1840. 

f Anat. Expos, of the Struct, of the Human Body, hy Winslow, Prof., &e. 
translated by Douglass, vol. ii. p. 117. London, 1749. 
% See Am. Joum. Med. Sci. April, 184G, p. 435. 



382 INTEGUMENTS. 

CHAPTER III. 
Of the Nails.* 

The Nails {Ungues) supply the place of cuticle on the extremi- 
ties of the fingers and toes, and may be considered as a continuation 
of this membrane, because in maceration they come off along with 
it. They correspond with the talons and hoofs of the lower orders 
of animals. 

Each nail consists of a root, of a body, and of a free extremity, 
or that which projects and requires paring. The root is about one- 
fifth of the length of the nail ; is thin, soft, and white, and is received 
into a fold or fossa of the true skin, which is very distinct when the 
cuticle and nail are removed together by maceration. The concave 
surface of the nail adheres closely to the skin below, precisely as 
the cuticle does in any other part of the body, and therefore may be 
loosened by the same processes, as hot water and maceration. The 
white part of the nail, at its root, is called the Crescent, (Lunula,) and 
is said, by Mosely,f never to exist in the fingers of Africans or of 
persons who have even a slight mixture of negro blood; the latter 
opinion I am disposed to consider incorrect. This appearance, 
however, does not depend upon any peculiar organization of the 
nail itself at that part, but upon the cutis vera below it, which being 
more vascular elsewhere, causes that spot to look white, the nail 
being semi-diaphanous and permitting a view of the circulation be- 
neath. This is also sufficiently proved by the fact, that when a 
nail is torn off, its lunula disappears. The nail increases gradually 
in thickness from its root to its free extremity. 

The nail is covered on the posterior face of its root by the epi- 
dermis, which terminates there in a thin, adherent, diaphanous 
band: behind this band the root of the nail projects, and is received 
into the groove of the cutis vera. The epidermis also adheres to 
the lateral margin of the nail, and in a curved line to the concave 
side of its anterior end. The under surface of the nail is soft, pulpy, 

* Anat. Atlas, Figs. 152 to 155, included, 
f Diseases of Warm Climates. 



THE NAILS. 383 

and has an arrangement of superficial longitudinal grooves, receiving 
the papillae and ridges of the corresponding surface of the cutis vera. 
As the black colour of the negroes is sometimes seen beneath their 
nails, it is probable, as stated, that the rete mucosum exists there 
also ; but it is not so clearly ascertained, though the observations 
of M. Gaultier, on the rete mucosum of animals, tend to prove it.* 

As the nails are entirely destitute of organization, having neither 
vessels nor nerves, they have no power of growth nor of disease 
in themselves, these qualities being derived exclusively from the 
cutis vera. The materials of their formation are, accordingly, 
secreted from the cutis vera, in the bottom of the groove, formed 
by the latter for the reception of their root. As these materials 
adhere to the preceding formation, and become concrete, by adding 
continually to its length, they shove it forward, and thereby elongate 
it. While this is going on in the groove, the thickness of the nail 
is also somewhat increased by an excretion from the skin contiguous 
to its concave surface. This accounts for the nail being thicker at 
its free extremity than at its root. 

The skin where it is in connexion with the nail exhibits numerous 
longitudinal fine ridges which make corresponding furrows into the 
nail; there are also small papillary projections. The end of the 
nail at its root is also finely serrated and the interspaces are filled 
with corresponding filiform papillae arising from the skin. These 
papillae are the sources of the growth of the nail by the continual 
secretion from them, and exhibit a close analogy with the arrange- 
ment at the roots of the hair. The microscope shows that the ori- 
ginal secretion is in the condition of soft nucleated cells, which are 
attached to their predecessors, and that this arrangement prevails 
every where over the adherent surface of the nail. The foetal period 
is the best for observing these nucleated cells. As the growth 
advances they assume the consistence peculiar to the nail. 

Owing to a peculiarly morbid state of the proximate surface of 
the true skin, it sometimes happens, that the contribution to the nail 
from it exceeds that from the groove; the consequence of which is, 
that the whole nail grows upwards like a horn, instead of forwards. 
An example of this kind was several years ago exhibited to me by 
Prof. Charles D. Meigs, in a white female, aged about ninety. In 
this case one of the big toe nails had grown upwards, in a semi- 

* See Rete Mucosum. 



384 



INTEGUMENTS. 



spiral manner, to the length of four and a quarter inches, when 
measured along the outer edge of the spiral. The corresponding 
nail of the other side would have been of nearly the same length, 
but it had been broken. The nails of all the other toes had as- 
sumed a similar manner of growth, and measured from one and a 
half to two inches. In the case of each nail its anterior extremity 
presented the primitive nail as it had been before this extraordi- 
nary hypertrophy. 

The statement of the patient was, that the growth had commenced 
about fifteen years previously. A tendency to this horny growth 
from the skin, was also manifested in a tubercle, three or four lines 
long, with an ulcerated base, from the back of her nose ; and by 
scaly excrescences on the legs. The patient having died shortly 
afterwards, the collection of nails was politely presented to the 
Anatomical Museum, by Dr. Meigs. 

I am indebted to my friend Dr. Theophilus C. Dunn, of Newport, 
Rhode Island, a graduate of this University, for a corresponding 
specimen where the whole foot was preserved, and sent on to me. 
The case was that of an aged black female, and the nails were the 
growth of many years, their length being very nearly equal to the 
preceding ; they had, however, kept in a direction forwards, and not 
vertical as the preceding, and were, therefore, more in the shape of 
plates.* 

In cases where the nail has been lost by violence or disease, the 
cutis vera secretes another ; but it differs from the first, unless the 
cutis vera has been restored to a perfectly healthy action : from this 
cause, we see in individuals thick black nails, sometimes cleft lon- 
gitudinally. 

The nails begin to appear about the fifth month of foetal life, and 
are still imperfect at birth. When analyzed, they seem to consist 
in coagulated albumen, with a small quantity of the phosphate of 
lime. 

* She had been an inmate of the Aims-House there, and died in the latter 
part of 1845. 



THE HAIRS. 385 



CHAPTER IV, 

Of the Hairs.* 

The Hairs (Pill, Crines) are cylindrical filaments, which are 
found on most parts of the skin, excepting the palms and the soles. 
The finest of them are microscopical, and have not a diameter ex- 
ceeding the one-sixth hundredth of an inch. 

The hairs differ much in their size and appearance in the several 
parts of the body. Those on the head (capilli, caesaries,) grow to 
the greatest length of any, and are most numerous in proportion to 
the space they occupy. Those which surround the mouth, and are 
on the cheeks, (julus, raystax, barba,) exceed the others in size, 
and when allowed to grow, are next in length, and more disposed 
to curl. Those around the eyes (cilia, and the supercilia,) are not 
disposed to exceed an inch in length, and have a long slender 
spindle shape. Those at the orifices of the nostrils and ears are of 
the same habits as the latter. Those of the arm pit, (glandebalae,) 
and about the organs of generation, (pubes,) are limited to the 
growth of a few inches. 

In the male subject there are hairs of considerable length, also, 
on the sternum, and about the nipples, an arrangement which seldom 
occurs in females. In most individuals, hairs are found over the 
whole remaining surface of the body ; but in females, and in many 
males, they are too fine to be readily visible. In some subjects, 
brought into our dissecting-rooms, the pilous system has been so 
developed as to form a shaggy coat over the whole body, and almost 
to conceal the skin. 

We are informed, on the authority of Jameson's Tour, of a man, 
at Ava, covered from head to foot with hair. That on the face and 
ears is shaggy, and about eight inches long; on the breast and 
shoulders it is from four to five. He is a native of the Shan coun- 
try, and married a Burmese woman, by whom he has two daugh- 

* Anat. Atlas, Figs. 147 to 151, inclusive. 
Vol. I.— 33 



386 INTEGUMENTS. 

ters: the youngest is covered with hair like her father, but the 
eldest resembles her mother.* 

In the female the hairs of the head are more abundant, and reach 
a greater length than they do in the male. As a general rule, the 
colour of the hairs corresponds with that of the eyes and of the 
skin, and the darker they are, the coarser. According to Withoff, 
a quarter of an inch square of skin has upon it 147 black hairs, 
while the same extent has 162 hazel, or 182 white ones, in other 
individuals. 

Each hair consists in a bulb and in a stalk. The bulb is the 
adherent extremity, and is whiter, softer, and generally larger than 
any other part; it is received into a follicle, compared appropriately 
by Malpighi to the vase containing a flower or plant, and which is 
deposited most commonly in the subcutaneous cellular substance, 
but sometimes in the skin itself. This follicle is of an oblong 
ovoidal shape ; its open orifice is continuous with the surface of 
the skin, while its internal end is closed, and has some filaments 
passing from it to the adjacent cellular substance. It is formed of 
two membranes ; the external is white, strong, and continuous with 
the derm or cutis vera; the second being within the last, is more 
soft, delicate, and vascular, and seems to be a continuation of the 
rete mucosum, or of the cuticle, if we are to consider, with the mi- 
croscopists, the two as identical, and the internal face of it is covered 
with delicate scales or cells. From the bottom of the cavity of the 
follicle, a small conoidal papilla erects itself towards the orifice. 
This papilla is vascular, and from the dissections of M. Beclard, 
on the human subject, and of M. Rudolphi, on the mustachios of 
seals, is furnished with nerves. The mode of approach of its vessels 
is not yet settled. M. Gaultier says that the arteries pass from the 
surface of the skin into the orifice of the follicle, and then descend, 
in a serpentine manner, between its two membranes to the bottom. f 
M. Beclard, on the contrary, considers them to pass through the 
bottom of the follicle. Each piliferous follicle is, moreover, 
furnished, within its orifice, with many small sebaceous follicles 
arranged round it. 

* Littell's Museum, No. 69; p. 412. 

f J. Cloquet, Anat. de l'Homme, PI. CXVIII. fig. II. 



387 

Fig. 14.* Fig. 15. f 




THE HAIRS. 



"Fig. 14. Pulp of a hair injected, after Hunter, in 
the Catalogue of the Museum of the College of Sur- 
geons, Physiological Series, vol. iii.— 1. Cut sur- 
face of hair ; 2. the pulp ; 3. injected vessel ramifying 
in it. 

" Fig. 15. Whisker of a walrus in its follicle, after 
Hunter, in the Catalogue of the Museum of the Col- 
lege of Surgeons : — 1 . C ut surface of lip ; 2. cutis ; 3. 
external sheath of the follicle ; 4. internal sheath con^ 
tinuous with the cuticle, which, both in the drawing 
and in the preparations which Mr. Hunter has left, 
is seen to line the follicle to the point of attachment 
of the bulb of the hair; 5. pulp or matrix; G. shaft 
of the hair: 7. Large nerve going to it." 



The bulb of the hair has in it, as seen, a conoidal cavity, open at its 
base and receiving the conoidal papilla of the follicle. The hair re- 
ceives its nourishment from the papilla by a successive deposite 
of nucleated cells just like a nail. The hair is moreover attached 
to the skin by the cuticle; for the latter having reached the orifice 
of the follicle is then reflected for some distance along the hair: this 
increases the strength of the attachment of the hair to the skin. 

The stalk of a hair has generally the loose extremity smaller than 
any other part, and frequently split. When examined with a mi- 
croscope the stalk appears to consist of two substances, one within 
the other. The exterior is a diaphanous sheath almost colourless, 
and, from having the properties of the epidermis, maybe a continua- 
tion of it. The microscope shows it to be formed on its outside 
by minute scales, resembling, but much smaller than those of the 
epidermis, and arranged into rows like the shingles upon a house, the 
free edges of which are sometimes transverse, and sometimes ob- 
lique or spiral. The interior consists of long filaments, parallel with 
one another, and forming a tube in the centre of the fasciculus. 
These filaments sometimes part spontaneously by the splitting of the 
envelope — and this may at any rate be accelerated by soaking the 
hair in dilute acid and crushing it. The tube, as well as the inter- 



* From Muller's Physiol, by Baly. 



f Ibid. 



388 INTEGUMENTS. 

slices between the filaments, is filled with a fluid called the marrow 
of the hair. This substance corresponds with one of the layers of 
the rete mucosum of the skin, and contains the colouring matter. 
The medulla appears to be formed of colourless cells, intermingled 
with pigment cells. The probability is, that the whole hair is a con- 
tinuation of the rete mucosum, and of the epidermis : whether we 
are disposed to consider these layers as distinct or as identical. 
The canal in the centre of the hair is found to be remarkably large in 
the hog*s bristle ; it is also well seen in the supercilia : the follicle 
and bulb are best studied in the mustachios of the larger animals. 
According to Mr. Heusinger,* the substance of the hair, when ex- 
amined with a microscope of strong po.wer, exhibits an areolar 
appearance. 

Though the stalk of the hair is destitute of blood vessels and of 
nerves, yet it is probable, from the sudden changes of colour that 
sometimes occur in it from black to white, owing to terror and grief, 
that there is a species of interstitial circulation going on. The ema- 
ciated and peculiar appearance which sickness gives to it, would also 
tend to support this opinion. Strictly speaking, the hairs are de- 
void of sensibility, yet, as the bulb is planted over a sensitive 
papilla, they communicate certain sensations by being removed or 
touched. Animals apply their mustachios particularly to this use in 
groping through dark places, or when they are deprived of sight. 
The hairs are eminently hygroscopic, moisture lengthens, and dry- 
ness shortens them ; this property has caused them to be applied to 
the construction of hygrometers. 

In certain animals the hairs are erected by the contraction of the 
subcutaneous muscle. The movement in the human subject corres- 
ponding with that, is the effect of great fright, and is produced by 
the contraction of the occipito frontalis muscle. 

In the development of hair, the part which first forms is the fol- 
licle, the young hair then pierces it at its summit, in the same way 
that the tooth pierces its capsule. The death of the capsule, or the 
drying up of its fluids, occasions the fall of the hair and prevents its 
regeneration. In old men who are bald there is no appearance of 
capsules ; while in persons from whom the hair has fallen owing to 
sickness, as the capsules still remain, they soon put forth another 
crop of hair. The rudiments of the hair are seen about the fifth 

* J. Cloquet, loc. cit. 



THE HAIRS. 389 

month of fetal life. The first crop is deciduous, and after covering 
the body of the fetus like a fine down, till the eighth month of utero- 
gestation, it then falls off: sometimes, however, it is retained either 
in whole or in part till after birth ; this is particularly the case in 
regard to the hair of the head. In this deciduous character we see 
another analogy between the hair and the teeth. 

When the hair becomes white from age, the conversion of colour 
begins at the loose extremity, another proof of the interstitial circu- 
lation, or change of particles in it. The same fact is observable in 
animals who change colour only for the winter. But the restoration 
of colour begins at the root. 

It is probable, in those cases of plica polonica attended with 
bleeding from the root of the hair when it is cut, that the vascular 
papilla has been so much augmented as to elevate itself above the 
level of the cuticle, and of course interferes with the sweep of the 
razor employed in shaving the head. Ignorance in regard to the 
organization of the hair, and a slight inclination to the marvellous, 
would magnify this into every hair, in such a disease, being a sort 
of branch-pipe from the general circulating system, and therefore 
bleeding upon being wounded. Many of the victims to this dis- 
ease accordingly prefer the loathsome matting of the hair with 
which it is accompanied, to the supposed risk of dying by hsemor- 
rhage. 



33* 



BOOK III. 

PART I. 

CHAPTER I. 
Histology of the Muscles.* 

The Muscles (Muscidi) by their contraction produce the various 
flexions of the body, and are, therefore, the organs of motion. They 
may be known by their redness, softness, irritability, contractility, 
and by their being formed of long parallel fibres. The redness,, 
however, does not always attend them ; as this colour is very faint 
in the foetus, and does not exist at all in animals that have not red 
blood. They form a very considerable share of the whole bulk of 
the body. 

Though the most perfect organs of motion, and producing it more 
efficiently and rapidly than any other apparatus, they are not indis- 
pensable to it ; for they are not observable in animals of a very low 
grade, which apparently consist of a sort of cellular or mucous sub- 
stance. In the next grade of animals, as the worms, where there 
is a deficiency both of bony and of cartilaginous skeleton, the mus^ 
cles are perceptible, and produce locomotion by their attachment to 
the skin or integuments; and, finally, in animals which have a ske- 
leton, the muscles are almost exclusively attached to its different 
points, and by alternately approximating them, effect locomotion. 

The muscles of the human body are referrible to two classes, in 

* These organs were very imperfectly known to the ancients, excepting 
Galen, and had not generally received names till the time of Sylvius, A. D. 
1587. The paramount authority of Albinus, in this department of Anatomy, 
in his work, Historia Musculorum Hominis, Leyden, 1734, has induced me to 
adopt it as the standard of correct description and nomenclature, with but few 
exceptions. 



392 MUSCLES. 

consequence of their position and functions, though they present a 
close similitude of structure every where. The most numerous class, 
as well as that in which they are of the greatest magnitude, are the 
muscles of voluntary motion, or of Animal life : they are placed be- 
tween the skeleton and the integuments, and constitute the principal 
bulk of the extremities, and also afford a thick fleshy covering to 
the trunk. The second class, being the muscles of Organic life, 
is contained within the large cavities of the skeleton, and forms a 
portion of the structure of the circulatory, of the digestive, and of 
the urinary organs. This set produces the principal internal motions 
of the animal economy. 

Every muscle is surrounded by an envelope of fibro-cellular sub- 
stance, called its sheath, (Membrana Musculorum Communis*) which 
at different points of the body exhibits various degrees of condensa- 
tion. In the muscles of voluntary motion these sheaths are formed 
by partitions, going from the aponeurotic expansions just beneath 
the skin, to the periosteum, and are the prolongations which in- 
duced Bichat to consider the periosteum, as the centre of the des- 
moid system. These sheaths in some cases preserve to a considera- 
ble extent the ligamentous appearance, but generally cellular sub- 
stance predominates in them. Upon their existence is founded the 
great variety of views and descriptions which the later anatomists 
have taken of the fascia? of the human body, some choosing to 
describe them in one way and some in another. The sheaths of the 
second class of muscles are composed of a much finer and looser 
coat of cellular substance than those of the first, and are commonly 
described as laminae or tunics to the organs to which they respec- 
tively belong. In every case, however, from the internal face of the 
sheaths, a great many partitions pass off, which penetrate the body 
or thickness of the muscle, and divide and subdivide it into fasciculi, 
and into fibres, even to their most minute condition. These parti- 
tions become thinner the more they are multiplied. 

Many of the muscles are subdivided by fissures, into several large 
portions called Fasciculi, or Lacerti. These vary very much in size, 
and in their distinctness from each other. Some are so large and so 
widely separated as to appear like distinct muscles ; such, for ex- 
ample, are the biceps of the arm and of the thigh, the deltoid, the 
columnar carnege of the heart, and several others. But the greater 
part of the fasciculi are strictly parallel with each other, and merely 

* Haller, Element. Physiol, torn. i. 



HISTOLOGY OF THE MUSCLES. 393 

separated by a thin lamina of cellular substance. The fasciculi are 
again subdivisible into fibres, which from their smallness are not ap- 
preciable to the naked eye, and, when examined with powerful 
microscopes, admit of farther division until we reach the primi- 
tive fibrillae. On this account some anatomists have undertaken to 
classify the fasciculi under the terms of first, second, and third 
orders. It is evident, however, that this arrangement is too arbi- 
trary, and that the circumstance is sufficiently expressed by con- 
sidering the fasciculi as almost indefinitely divisible. The fibrous 
arrangement of muscles is rendered still more distinct by boiling 
them, or by immersing them in alcohol. 

The structure of the muscular fibre has been studied with great 
attention by microscopical observers. From such observations, it 
appears that their ultimate shape is prismatic, pentagonal, hexa- 
gonal, sometimes rounded* 



MUSCLES OF ANIMAL LIFE.* 

The present state of the minute anatomy of the muscles of animal 
life, points out the following conditions : — The fibres are arranged 
with great regularity and in parallel lines, so far as individual fas- 
ciculi are concerned. The smallest fibre visible to the naked eye, 
is by the microseope ascertained to be itself formed of subordinate 
fibrillse of a cylindrical or polygonal shape, and closely applied to 
each other. In order to see the primitive fibrillse, or those which 
admit of no farther division, the best way is to take the smallest 
distinct fibre and pull it apart in its length, its transverse rupture 
will then show by the microscope a finely divided filamentous end, 
these filaments, from the incapability of a farther separation, are con- 
sidered as being the ultimate fibres. This faseis is held together by 
a sheath of its own, called the Myolemma, or Sarcolemma,f which 
is conceived to have a texture different from common cellular sub- 
stance, and consists of a transparent, very delicate, but strong and 
elastic membrane, which insulates the faseis from every kind of con- 
tiguous structure. The Sarcolemma is amorphous, or has no formal 
texture generally, but in the case of very large fibres it has an indis- 
tinct evolution of filaments which are interwoven. It has also some- 

* Anat. Atlas, Fig. 156 to 1G5 inclusive, 
f Tod & Bowman, p. 155. 



394 MUSCLES. 

times in contact with itself small corpuscles, the remains of cell nuclei. 
The sarcolemma of a muscular fascis is occasionally upon the rupture 
of the latter left entire, which is a good way of studying it, in which 
case there is some resemblance to a small sword broken in its scab- 
bard ; another good way to see it, is by maceration, which, by 
causing the muscular fascis to swell, ruptures the sarcolemma in 
spots, so as to resemble hernia. It is considered to have nothing 
to do with either the longitudinal or transverse striae of muscles, and 
not to be even perforated by the nerves, or by the capillary blood 
vessels. 

A question still unsettled, is whether one of those smallest mus- 
cular fasces is solid, or has a hollow in the midst of its ultimate 
fibres. The fascis of the human muscle is from about the two hun- 
dredth to the six hundredth part of an inch in diameter. It is larger 
in reptiles and in fish than in other vertebrata — it is smallest in birds, 
and what is remarkable, it observes no proportionate size to the 
species. Thus it is larger in the Chaffinch than in the Owl, in the 
Cat than in the Horse, in the Frog than in the Boa, and in insects 
generally larger than in mammalia.* 

The primitive or ultimate fibrillse have a diameter, according to 
Wagner, of from about the 9.000 to the 11.000 part of an inch, and 
are said by him to be of nearly the same dimensions in all vertebrate 
animals, in insects and in craw-fish ; from five to eight hundred of 
them compose a fascis of muscle as surrounded by its sarco- 
lemma. 

A fascis under the microscope, exhibits upon its individual fibrillse a 
succession of light and dark spots in the case of the muscles of ani- 
mal life. These spots are now admitted to be the result of a chaplet 
or bead-like condition of the ultimate filament; and an idea has 
been advanced by Mr. Bowman that the filaments are subject to a 
transverse cleavage, bearing no inconsiderable resemblance to a pile 
of coin, or of any flat circular disks. 

The varicose or bead-like muscular fibre is found in all muscles 
subject to the will, and also in the pharynx, oesophagus, and in the 
heart. In the oesophagus it is blended with the smooth muscular 
fibre, or that of organic life, being found at various distances down 
this tube in different individuals, in some of whom it reaches to 
within an inch of the stomach. 

Such being the present state of microscopical observation on the 

* Carpenter Princ. of Phys. p. 291. 



HISTOLOGY OF THE MUSCLES. 395 

anatomy of the muscles, it is remarkable how closely the truth was 
approximated by the earlier descriptions. 

Among the first efforts to settle this point are those of Hook, com- 
municated to the Royal Society of London, about the year 1678. 
Having reduced into filaments the muscles of the cray-fish, he ob- 
served that they resembled strings of beads or chaplets, and did not 
exceed in diameter the hundredth part of a hair.* A fasciculus of 
them, the size of a hair, looked like a necklace, composed of seve- 
ral strings of pearls. Leeuwenhoeckf considered the muscles to 
consist of prismatic bundles of filaments, these bundles being sepa- 
rated by thin membranes and called by him secondary fasciculi. The 
filaments themselves formed the primary fibre, and were also sepa- 
rated by very thin membranes ; their diameter he estimated at about 
the two thousandth part of a line. These he called striae carnosse, 
and learned that in insects they made inflections during the repose 
of the muscle, and which disappeared when it was in an active state. 
The stria; carnosse had to him the appearance of being composed of 
globules, which he had some difficulty in distinguishing from the in- 
flections or wrinkles. The primary fibre, small as it is, he thought, 
consisted of a great number of still more delicate fibres, which he 
called fibres intimae. 

Prochaska^ divides also the muscles into three orders of bundles 
of fibres — the first, second and third, which are respectively kept 
asunder from their fellows by sheaths of cellular substance pene- 
trating from the general sheath of the muscle. In the third order, 
or that of the primitive fasciculi, the fibres, he says, are flat, of a 
thickness somewhat unequal and run out the entire length of the 
muscle, even in the sartorius. These fibres are composed of ulti- 
mate filaments of a prismatic shape, and whose diameter is about 
the eighth of a corpuscle of blood, which estimating at the three 
thousandth part of an inch, his measurement corresponds with that 
of the striae carnosae of Leeuwenhoeck. He witnessed also the un- 
dulations of the fasciculi and of the fibres, and attributed it to the 
pressure of filaments of cellular substance, of vessels, and of nerves 
which traversed their surface. 

Fontana§ gave especial importance to the transverse stria?, which 

* About the six hundredth part of an inch. 

f Opera, T. i. ii. iii. 

£ De came musculari, 1778. 

§ Treatise on the poison of the Viper, T. ii. 



396 MUSCLES. 

had been seen by others upon the primitive fasciculi, by considering 
them to be the points of junction of the segments of the primitive 
fibres, for the latter, he said, were interrupted at equal distances by 
lines which looked like globules, and might indeed be mistaken for 
wrinkles. The latter opinion was entertained by Treviranus so late 
as in 1816. 

The transverse strise are very numerous in the human subject, 
there are from six to fifteen of them in the hundredth of an inch, 
their distance there is about two to five diameters of a globule of 
blood, fixing the latter the 30W of an inch. 

In meat which is prepared for the table by roasting or boiling, 
or in a muscle which is contracted, one frequently sees the fibres 
undulated or crooked. By Prochaska, as just stated, it was attributed 
to the bridling of the fibre, by the contraction of its cellular substance, 
nerves, and blood vessels. The cause, however, is not well as- 
certained: the condition seems to be one of the peculiarities of mus- 
cular fibre, which it manifests when in a state of contraction only ; 
for it disappears whenever the fibre is relaxed, either by spontaneous 
movement, or by stretching it in the dead body. This undulation 
has probably contributed to the many inexact observations on the 
structure of muscles. Thus, Haller thought they consisted in a 
series of ovoid vesicles, which lengthened in a state of relaxation, 
and became more globular in a state of contraction. It is unneces- 
sary to dwell on mere errors of the eyes or of the imagination, for 
the fact seems to be now well established, that, though the muscular 
fibre, by contracting, loses its straightness and becomes crooked, 
yet this is effected without change in the form of the ultimate 
globules of which it consists. 

Among the approved accounts, of the ultimate structure of mus- 
cular fibre, are those of Mr. Bauer, with Sir Everard Home ; and 
of MM. Prevost and Dumas. These gentlemen concur in stating 
that the results have been uniform in all animals to which their ob- 
servations have been extended. That the muscular fibre is a series 
of globules, resembling the globules of the blood deprived of colour- 
ing matter and adhering in a line to each other. That the medium 
of adhesion is invisible from its transparency and want of colour ; 
but if the muscle be macerated in water frequently changed, that 
this medium, from its greater solubility and more ready putrefaction, 
may be removed so as to leave the globules detached from each 
other, and still resembling the globules of the blood. The fact of 



HISTOLOGY OP* THE MUSCLES. 39! 

the globular condition of the muscular fibre, as stated, was pointed 
out by Leeuwenhoeck and Hook; it is also approved by the testi- 
mony of M. Milne Edwards and M. Dutrochet. 

The opinions of the still more recent observers are but slight mo- 
difications of the preceding, and it is perceived that the basis of them 
was evidently laid by Leeuwenhoeck, and by Hook. Many micro- 
scopical observers have entered, since 1830, the lists for the purpose 
of elucidating this structure, an attention to them all would be a history 
of opinions incompatible with the limits of a class book.* Some 
few may be quoted. 

Muller,f in admitting the beaded arrangement, says, however, 
that it is incorrect to consider it as the result of a mere aggregation 
of globules, because there is a distinct continuation of fibre from 
one knot to the next. GerberJ admits the granular appearance of 
the primary fibres, but says, that it seems to depend on very short 
sinuous bendings. 

The results of a very protracted and careful investigation of the 
matter by Dr. Schwann, are, that the diameter of the primitive fas- 
ciculus varies from the 5V to 5 V of an English line. The primitive 
fibres of a rabbit, which he asserts to be the most suitable animal for 
such an inquiry, he says, are bead-like filaments, presenting a series 
of dark points ; these points being in the bead-like enlargements. 
He considers the appearance of transverse striae to be produced by 
the dark points on the primitive muscular fibre. These points are 
at uniform distances from one another in the same primitive fasci- 
culus, but may be very different in other and even Contiguous fas- 
ciculi^ 

This bead-like state of the muscular fibre is recognised also by 
Henle,|| who lays down the rule that all muscles attached to the 
skeleton have this varicose condition. 

Notwithstanding the value and number of the authorities in favour 
of this knotted state of the primitive muscular fibre in the muscles at 
least of animal life, highly reputable testimony is opposed to it. Va- 
lentin considers that the primitive fibres, in a state of repose and of 
health, are straight and homogeneous, but become varicose while in 
a state of contraction. He says, that thin alternate elevations and de- 

* For information consult Traite d'Anatomie Generale, par J. Henle, p. 158. 
Paris, 1843. 
f Physiol, p. 879. X Gen - Anat - P- 240 > text - 

§ Miiller Physiol, p. 881; |j Anat. Gen. p. 129, T. 2d* 

Vol. I.— 34 



398 MUSCLES. 

pressions on their circumference cause a bead-like appearance, either 
from its being the result of a special vaginiform condition, or from its 
being merely the exterior layer of the primitive filament. The central 
portion of the latter, he concludes, from the result of his microscopic 
observations, to be uniformly cylindrical. 

Treviranus considers the knotted condition of the muscular fibres 
to be no other than granules, adhering to their exterior surface ; such, 
at least,- is the result of his observations upon insects. According to 
Fieinus, the fresh muscular fibre is straight, and it is upon death that 
it is resolved into a chain of distinct globules ; the latter, indeed, 
may be simulated by the simple inflections of the muscular fibre. 

Krause, after holding the opinion of the bead-like state of the 
muscular fibre, has more lately* retracted the idea under the declara- 
tion that this irregularity is due to the commencement of putrefac- 
tion, and that it is unusual to see it upon fresh fibres at the beginning 
of a dissection. 

By some it has been asserted that muscles are only the continua- 
tion of blood vessels. To this it is replied,! that though insects 
have muscles, yet they have not blood vessels, so that the former 
cannot be a continuation of the latter. Moreover, a successful in- 
jection, though it may penetrate very finely between the fibres, so 
as to cause the muscle to swell considerably, yet none of these 
vessels can be traced into the ultimate fibre ; the blood vessels there- 
upon do not penetrate the myolemma, and consequently the ultimate 
muscular fibre is free from blood vessels, the latter being only con- 
tiguous to it. The vital phenomena and the organization of mus- 
cular fibre, are so very different from cellular substance, from 
nerves, and from vessels, that it cannot be less than a distinct 
structure. 

Notwithstanding this limitation, which is put upon the distribu- 
tion of the blood vessels, every muscle is abundantly supplied by 
them. The arteries come from the adjacent large trunks, and pene- 
trate at different points of the periphery of the muscle. They first 
of all pass between the larger fasciculi and parallel with them ; they 
then divide and follow the course of the smaller fasciculi; they 
divide and subdivide again after the same rule, till they become 
mere capillary tubes, from which the nutritive matter is exhaled. 
The veins accompany the arteries, and receive their blood ; some 

* Henle, ut supra, p. 158, vol. 2d. 
j- Beclard, Anat. Gen. 



HISTOLOGY OF THE MUSCLES. 



399 



Fig. 16, 



•of them creep along the surface of the muscle without having cor- 
responding arteries. Bichat says truly that they are injected with 
great facility from their trunks, from which he supposes that their 
valves are less numerous than in other parts of the system. 

The colour of the muscular fibre seems 
to be, in a measure, independent of the 
blood which circulates in it. Some ani- 
mals with red blood have white fibres, 
as frogs. The colour of the muscular 
fibre is not altered in animals that have 
been suffocated. The muscular fibres of 
the intestines and of the bladder, though 
abounding in blood vessels, are whiter 
than the muscles of voluntary motion. Capillary network of Muscle. 




Lymphatics have been injected in the intervals between con- 
tiguous muscles and between their fasciculi. 



The Nerves of the muscles are large and abundant, as the nerves 
of the brain and spinal marrow are chiefly spent upon them. They 
are generally proportioned to the size of the muscle which they have 
to supply, but there is some variety in this respect. They accom- 
pany the arteries, and are united to them by cellular substance. 
Their ultimate terminations are traced with great difficulty, and there 
is consequently an uncertainty on this subject. Before they dis- 
appear they become soft by divesting themselves of their cellular 
envelope, and are supposed to bring thus their medullary substance 
in immediate contact with the muscular fibre. The recent observa- 
tions of MM. Prevost and Dumas, are thought to throw some light 
on this matter, and have been received with a very respectful atten- 
tion. They say, that by maeerating in clean water, and in a dark 
place the muscle of a bullock, and then throwing a strong concentrated 
light upon it, the distinction of colour between the nerves and the 
muscular fibres becomes very apparent. With the aid of a microscope 
and a fine knife, the nervous ramifications may be then traced. The 
trunk of the nerve enters the muscle parallel with its fibres, and soon 
begins to give off', at right angles, lateral filaments, which penetrate 
between the fasciculi and fibres of the muscles, and may be followed 
to the top of the undulations formed on the muscular fibres. These 
lateral filaments at some places are two in number, which pass at 
some distance from each other, but parallel, and terminate by an 



iOO MUSCLES. 

interchange of filaments; at other places the terminating branches 
are spread out transversely to the muscular fibre, and end by forming 
loops with themselves. According to this view, the nervous fila- 
ments, strictly speaking, have no termination, but run again into the 
source from which they are derived.* 

The transverse spiral lines, looking like filaments or threads sur- 
rounding the muscular fibres, and considered by some, as a cleavage 
in them may possibly be the final wrapping of the nervous fila- 
ments around the muscular fibre, as in my observations, an injec- 
tion with the salt antiseptic mixture,! destroys this feature probably 
by the solvent action of the alkali, on the neurine. 

The chemical analysis of muscles shows them to be composed of 
fibrin, albumen, gelatin, | extractive matter, the phosphate of soda, 
ammonia, and of lime, and of the carbonate of lime. The extractive 
matter of the muscle may be removed by maceration, in clean water 
often changed. If it be allowed to remain long, it assumes certain 
appearances in its putrefaction peculiar to itself, but occasionally it 
!s converted into a substance resembling spermaceti. When a mus- 
cle is exposed to boiling water, the albumen is raised to the surface, 
like foam ; the gelatin coagulates when the muscle is cold ; and the 
fibrin appears as a fibrous grayish substance, insoluble in hot water, 
closely resembling the fibrin of the blood, and evolving large quan- 
tities of nitrogen by the action of nitric acid. When a muscle is 
exposed to the fire alone, as in roasting, the albumen is hardened; 
the gelatin is melted, and runs off, in part, w T ith the juices of the 
meat ; the extractive matter is that which gives a dark colour to the 
outside, the fibrin is cooked in the juices of the meat, and is then 
rendered very tender. The muscular parts of animals are amongst 
the easiest of digestion. 

The muscular system of the embryo is first of all in a gelatinous 
state, and confounded with cellular substance; but at two months 
from conception, the fibres are distinct, and at four they begin to 
contract and to execute different motions. 

In the development of muscular fibre, it is ascertained that the 
Myolemma is first formed, and that by a file of cells placed end to 
end, which are converted into a tube by the removal of the partitions 

* Anat. Atlas, Fig. 16G. 

f Amer. Jour. Med. Sciences, Jan. 1845, p. 245. 

t Whether gelatin is to be considered as an ingredient of pure muscular mat- 
ter appears to be now doubted. 



HISTOLOGY OF THE MUSCLES. 401 

made by the ends of the cells. The nuclei of the cells are visible 
for some time after the muscular fibre is formed, but they finally be- 
come indistinct as the fibre obtains the matured state, and can only 
be exhibited by particular management. They are supposed to act 
as centres of nutrition and reparation, their activity being propor- 
tioned to the activity of the muscle itself. 

The muscular system is subject to varieties of conformation. 
Robust, muscular individuals frequently have supernumerary mus- 
cles and supernumerary heads to their muscles, particularly in the 
extremities. In monstrous foetuses it sometimes happens that the 
muscular system is either wholly or partially supplanted by adipose 
matter and by infiltrated cellular substance. 

The Muscles of Organic Life, have one very plain distinction from 
those of Animal Life, their fasciculi have frequent anastomoses, and 
are interlaced in a retiform manner one with another, instead of 
continuing distinct and in parallel lines. The primitive fibre is, ac- 
cording to Dr. Schwann, about j,^ of an English line in diameter. 
These fibres are also destitute of the transverse striae, so remarkable 
in the muscles of animal life. They are almost perfectly smooth, 
are collected into flattened bands, and are of a light drab colour. 
Here and there, small inequalities or swellings exist, coming from 
elongated corpuscles, the nuclei of their formation, adhering to them. 
The fascis formed by the bundle of primitive fibres, measures in its 
transverse diameter, from the j,^ to the 5,^ of an inch,* and is, there- 
fore, from the half to the third of a blood corpuscle, taking the latter as 
the unit of measurement. Valentin and Tod do not admit the in- 
terlacement of these fibres ; the latter considers the appearance as 
the result of the elongated corpuscles throwing parts of the fibre out 
of focus ? and thus producing a confused reticulated figure. He also 
doubts that these fibres are invested by a sarcolemjna, as he says 
none has been discovered in an unequivocal manner. 

The muscles of organic life are soft, transparent, and, for the 
most part, deeply seated. The boundaries of their fibres are very 
faint, and though cylindrical of themselves, yet their fasciculi are flat 
or prismatic from pressure. The fibres are seldom in lines perfectly 
straight, but are for the most part bent in a serpentine way, or even 
crimped like the unravelled yarn of a stocking. The arrangement 
of the fibres has some resemblance to a fine nervous plexus, ancj 

* Tod and Bowman, 
34* 



402 • MUSCLES. 

within their meshes are placed mucous glands and other objects. 
Where the muscular matter is abundant, as in the bladder or the 
womb, it is arranged into layers, the constituent filaments and fas- 
ciculi of which, cross respectively at acute or right angles. 

The muscles of organic life are supplied with soft grayish nerves, 
mostly of the motory description, and also with blood vessels. 
Their primary filaments are not penetrated by either, but the latter 
are received into the interstices of their fasces and fasciculi. 

It is asserted that the Trichina Spiralis, a small worm not unfre- 
quently found in the muscles of animal life, is seldom or never 
in those of organic life, so that a definite line is thus established be- 
tween contiguous parts, as the inferior constrictor muscle of the pha- 
rynx and the top of the oesophagus.* 



CHAPTER II. 

8n Muscular Motion. 

The muscles, after death, are soft, easy to tear, and have but little 
elasticity ; it is only during life that they manifest such extraordi- 
nary strength, and retain their powers of motion. The general phe- 
nomena of the latter have been happily expressed by the word myo- 
tility, suggested by M. Chaussier. These phenomena are, contrac- 
tion, elongation, and, according to Barthez, a power of remaining 
motionless or fixed. 

In contracting, the muscle shortens, swells and becomes hard ; 
presents wrinkles on its surface ; and its fibres are sometimes thrown 
into a state of oscillation or vibration, from their alternate relaxation 
and contraction. It is owing to the vibratory motion in the fibres 
of a muscle, during their contraction, that a rustling is heard on the 
application of the stethoscope to them. The hollow, distant rum- 
bling when the meatus externus is closed by the finger, is owing to 
the same vibration in the muscles of the finger employed. This is 
readily proved by the following experiment : close the meatus with 

* Carpenter's Princ. of Physiol., p. 299, 



MUSCULAR MOTION. 403 

the end of the handle of an awl or a fork, pressed against it by the 
finger, and it will be found that the muscular vibrations are conti- 
nued along the instrument : plant, afterwards, the point of the instru- 
ment upon a soft, inelastic substance so as to make, in that way, the 
closure of the meatus, and the rumbling will instantly cease. The 
roaring noise of sea-shells may be explained in the same way. The 
colour remains the same, which proves that there is not an appre- 
ciable addition to the quantity of the circulating fluids. The rapi- 
dity with which this contraction may take place, is manifested in 
speaking, in running, and in playing upon a stringed instrument; 
and its strength, by the immense burdens that some individuals can 
raise and bear. 

The capability of the muscles to endure continued action, is ex- 
hibited daily along the wharves of Philadelphia, through the following 
statement from an experienced merchant : — a corn carrier between 
the ages of 18 and 30, can carry 21,000 lbs of corn up a height of 
35 feet in a day, by the following method. He carries two bushels 
of 120 lbs weight, up stairs and returns to the wharf in about three 
minutes. In each day he goes up stairs 175 times and descends 
as often — mounting in each instance thirty five steps, and elevating 
350 bushels by this process. In addition to this he elevates the bag 
to his shoulder and again discharges his load — which he usually 
carries at a run, and traverses some 60 feet of wharf and as much 
more of store room. This labour is done barefooted, and continued 
off and on, for a period of about seven years, when exposure and 
intemperate habits, generally kill him and his gang. 

The power of elongation or relaxation seems to be an active state 
of the muscle, as well as its contraction. This power of relaxation 
or of elongation is much inferior to that of contraction ; it seems to 
be only what is sufficient to restore the muscle to its proper length, 
so as to put it in a condition for the removal of its contractions. 
The fixedness of muscles, which are contracted spasmodically, and 
their retaining this position even after death, until putrefaction 
begins to assail them, shows that the power of elongation does not 
depend simply upon elasticity ; for the latter quality being as much 
the attribute of dead as of living matter, would be brought into play 
on death. 

The fixation of muscles is not a distinct power, but merely a 
qualification, of contraction, by which the latter may be arrested at; 
any given point, and retained there.. 



404 MUSCLES. 

As every muscle augments in thickness during its contraction, it 
has been a subject of inquiry to physiologists whether the whole 
mass of muscle was increased or diminished by its contraction. 
Swammerdam, in order to ascertain it, put an insulated solid muscle, 
not yet dead, into a tube filled with water ; by irritating the muscle, 
and causing it to contract, the w 7 ater descended ; but this result was 
not uniform. When an arm is plunged into a tube properly formed 
and filled with water, if the muscles be caused to contract, the fluid 
descends; but the objection to the inference from this experiment is, 
that when all the muscles of the arm are caused to contract violently, 
the introduction of arterial blood is much arrested, if not fully stop- 
ped ; and the venous blood is at the same time expelled : so that the 
change in the size of the member may be accounted for in that way. 
The experiments of Erman on eels, fully immersed in a fluid, and 
submitted to galvanic influence, are said to substantiate the theory 
of the muscles diminishing in bulk by contracting.* 

The activity of a muscle, though closely depending upon the afflux 
of blood to it, is not entirely so ; for it is ascertained that galvanism 
will cause the muscles of frogs to contract, when the circulation is 
arrested by death, or when the blood is coagulated, or even when it 
has been drawn ofT.f This phenomenon, however, can only last a 
comparatively short time ; for a muscle soon dies, and runs into a 
state of putrefaction, after its vascular and nervous communications 
have been cut off. Physiologists have entertained very different 
opinions on the causes of the muscles contracting, or on muscular 
irritability, as it is called. Some have supposed it to be an attribute 
of the muscle itself ; J others, that it depended on the blood vessels, 
which, by bringing a greater afflux of fluids into its interior, between 
its fasciculi and fibres, obliged the latter two to take a more flexuous 
course; and others, on the nerves. § Any decision on this point is 
inconclusive, because it is well known that perfect muscular action 
requires a healthy state of the muscle, and an uninterrupted nervous 
and sanguineous influence ; so that it seems to be a result from the 
combination of three systems, more than an attribute of one alone. || 

* Beelard ; loc. cit. 

f Prochaska de Came Musculari. Vienna, 1778. 
X Haller, Physiol. 
§ Legallois, sur le principe de la vie. 

|| Meckel Anat. Gen. ; from Barzellotti, Esame di alcuni moderne teorie 
internoalla causa prossima della contrazione moscolare, 1796. 



MUSCULAR MOTION. 405 

MM. Dumas and Prevost say, that in consequence of the final 
nervous ramifications crossing the muscular fibres at right angles 
to them, and parallel with one another, the galvanic current which 
passes through these ramifications, causes the latter to approach 
each other reciprocally ; whereby the muscular fibres to which the 
ramifications are fixed, are thrown into wrinkles. It is clear, from 
this theory, that the muscular fibres themselves are destitute of the 
power of contraction, and that they are only the frame-work 
upon which the Galvanic batteries of the nervous system are dis- 
played. 

For a farther exposition of these phenomena, and of the opinions 
on muscular contraction, the reader may consult with advantage, 
the approved modern treatises on Physiology.* 

There are no muscles which have not the power of contracting 
some time after apparent death, and this phenomenon frequently 
continues for an hour ;f it is uncommon for it to cease with the ap- 
parent extinction of life. This irritability is of different durations 
in the different muscles ; it is first lost in the left ventricle of the 
heart ; then in the large intestines ; afterwards in the small, and in 
the stomach ; then in the bladder, then in the right ventricle, the iris, 
and in the voluntary muscles; of which those of the trunk die first, 
those of the inferior extremities next, and those of the superior last. 
The last act of life is in the auricles, of which the right pulsates 
longest. Different circumstances may produce some variety of this 
progress in the loss of muscular irritability, but it will be found 
generally correct. J The experiments of Himly§ demonstrate, that 
laurel water, or that of bitter almonds, applied to the stomach or 
brain, renders the heart insensible to the strongest stimulants, while 
the muscles of volition continue to move for some hours afterwards. 
The duration of irritability is, however, much varied, according to 
the nature of the death, and the state of health preceding. Nysten 
asserts, that he has seen the right auricle of a robust man pulsate 
nine hours after death. In death from chronic diseases, with much 
emaciation, the heart ceases to beat shortly after intellectual pheno- 
mena cease. And in death from electricity ; from a blow upon the 

* See Miiller, Dunglison, Carpenter, Tod and Bowman, also Gerber's Gen. 
Anatomy. 

f The late visitation of cholera in Europe and in this country, gave to many 
persons an opportunity of examining this singular fact. 

% Meckel, Anat. Gen. § Commentatio de Morte, Goettingue, 1794. 



406 



MUSCLES. 



stomach ; from the inhalation of carburetted hydrogen gas, and some 
other poisonous ones, muscular contraction ceases universally in a 
few moments, and cannot be excited by any artificial means. 

The irritability of the muscles is so modified that certain stimu- 
lants are peculiarly appropriate to one and not to another. For 
example, light is the specific stimulant to the iris, a mechanical 
application to it, as in making an artificial pupil, is borne frequently 
without its contracting. The heart is very sensible to mechanical 
stimulants, and additionally so when they are applied to its internal 
surface. 

Some of the muscles are regularly under the influence of the will, 
others not at all so, which has given rise to their division into the 
voluntary and involuntary. These states, though kept perfectly 
distinct from each other in health, are sometimes blended in dis- 
ease, the voluntary muscles becoming involuntary in their actions, 
and the involuntary voluntary; which, however, is much more un- 
common than the other. 

The voluntary muscles being generally such as serve for locomo- 
tion and speech, receive their nerves directly from the spinal 
marrow. The involuntary muscles are such as are concerned in 
the functions of digestion, respiration, and circulation, and which, 
in order to continue the life of the animal, must never cease their 
actions for any long interval. It is worthy of remark, that apoplexy 
and other cerebral affections, paralyze, most commonly, the volun- 
tary muscles alone, while the others retain their usual state and 
sensibilities. 

When irritability is entirely gone from a muscle, and it is actually 
dead, the whole muscular system becomes stiff", beginning with the 
trunk, then the inferior, and, lastly, the superior extremities. This 
stiffness seems to be independent of the nervous system, as the de- 
struction of the spinal marrow, the cutting of nerves, and hemiplegia 
do not arrest it. It is thought, by M. Beclard, to be analogous to 
the contraction of the fibrine of the blood; and, like the latter, does 
not cease till putrefaction begins. The degree, as well as the time, 
of its access is variable under different circumstances. In very 
aged persons; in such as have died from protracted disease attended 
with great emaciation; in scorbutic and gangrenous diseases, the 
stiffness comes on quickly, is very slight, and disappears in a couple 
of hours. But in muscular subjects who have died from sudden 
violence or from acute diseases, the stiffness Is sometimes postponed 



VOLUNTARY MUSCLES. 407 

for twelve hours or more, and may continue, in the winter, from 
three or four days to a week, or even longer, depending upon the 
access of putrefaction. 

The sensibility of the muscles is moderate. When they have 
been much exercised, they only give out the sensation of fatigue. 
In amputations, the pain of cutting through them is not equal to 
that of the skin. In inflammations they, as most other parts, have 
their sensibility exalted to an exquisite degree. 



CHAPTER III. 
Of the Mechanical Shape and Arrangement of the Voluntary Muscles. 

Every muscle consists in a belly and in two extremities, of which 
the one that is the fixed point is the head or origin, and the other is 
the tail or insertion. The belly or body is the fleshy part, the ex- 
tremities are generally tendinous, either completely or partially. 

Some of the muscles arise by a single head, and are inserted into 
one point. Some few arise by a plurality of heads, but have a 
single insertion, as the biceps flexor of the arm, and of the thigh ; 
others, again, have a single head, but a plural insertion, as the 
flexors of the fingers and of the toes; others, again, have multi- 
plicate heads and multiplicate insertions, as the muscles of the 
back. 

The most simple muscles are such as have their fibres running in 
the direction of the length of the muscle, of which there are many 
examples, as the sartorius, the biceps flexor cubiti, the semi-tendi- 
nosus, and others. Others, again, have their fibres running obliquely 
from a tendon or a bony origin on one side of the muscle, to a ten- 
don on the other, as the semi-membranosus, the peronei, &c. ; these 
are called musculi semi-pennati. Others have a long tendon in the 
centre, to which the fibres converge obliquely, forming an angle with 
each other; they are the penniform, (musculi pennati.) Others, 
again, are formed of a congeries of smaller muscles, the fibres of 
which riin in different directions and are intermixed with tendinous 
matter, as the deltoid and subscapular. As the strength of a muscle 



408 TENDONS. 



depends upon the number of its fibres, those whose fibres go ob- 
liquely are stronger than if their fibres had run longitudinally. 



CHAPTER IV. 

Of the Tendons, (TcndinesO 

The tendinous extremities of muscles, present themselves under 
two general shapes : one is funicular, or like cords, varying in shape 
from cylindrical to paraboloid ; the other membranous, and resem- 
bling an aponeurosis. They both adhere with great tenacity to the 
muscular fibres, so as to have induced, erroneously, the opinion of 
absolute continuity : but maceration and boiling will separate them, 
and the course of the fibres is different even to the naked eye ; be- 
sides the very obvious difference in colour, in consistence, and in 
vital properties.* 

TSie tendons are surrounded by a loose cellular membrane or 
capsule, which permits them to glide freely upon each other : in 
some places this membrane is wanting, and is supplied by a synovial 
membrane answering the same purposes. 

The tendons are readily recognised by their white and shining 
appearance ; they have no elasticity or power of elongation and 
contraction, and, therefore, like other ligamentous matter, they are 
lacerated sooner than they can be stretched. They are composed 
of desmoid tissue, the fibres of which are united by a compact cel- 
lular substance in small quantities. The fibres are longitudinal, and 
may be readily separated either by maceration or by a slight boiling. 
When a round tendon is prepared in this way, it is easy to flatten it 
out into an aponeurotic membrane : the fibres are then made very 
distinct, and seem to adhere to each other by lateral fibrillse. In 
ordinary health no red blood penetrates into the tendons, but if they 
become inflamed, as their cap : llaries then enlarge, they admit the 
red globules ; at the same time their sensibility, from being entirely 

* Anat. Atlas, Fig. 1G5. 



THE TENDONS. 409 

organic, or what is only sufficient for the internal actions of the 
organ, is so much augmented as to be very manifest.* No nerves 
have been satisfactorily traced into them in the human subject. The 
tendons have the character, at large, of the desmoid tissue, but are 
more gelatinous, or completely soluble in boiling water, than the 
ligaments. They have a great affinity for the phosphate of lime ; 
and, hence, we frequently find them hardened and having small 
pieces of bone in them, where they run over bony trochlea?. 

* A knowledge of the disposition in tendons to augment their powers of 
circulation on being inflamed, together with the late Dr. Physick's, great suc- 
cess in the treatment of false joints by a seton passed through the cavity 
of the fracture, induced me in a tour of service at the Philadelphia Hospital 
to try the effect of a similar plan upon a ruptured tendo-achillis ; which, from 
the long period since the accident had happened, did not promise a cure on the 
ordinary methods of treatment. A seton of silk riband was accordingly in- 
troduced, and kept in its place for six weeks and a-half. It produced consi- 
derable pain, tumefaction, and inflammation, but was followed by a perfect re- 
union of the ruptured ends of the tendon. — See Chapman's Med. and Phys. Jour- 
nal, for July, 1826. For a highly interesting series of experiments on animals, 
undertaken at my suggestion, to illustrate the same thing, see An Essay for 
the degree of Doctor of Medicine, by R. L. Fearn, Id. April 9, 1827- 



Vol. I.— 35 



BOOK III* 

PART II. 

SPECIAL ANATOMY OF MUSCLES. 



CHAPTER I. 
Muscles of the Head and Neck. 

SECT. I. — MUSCLES OF THE FACE.f 

Occipito -Frontalis . 

The occipito-frontalis, a single muscle, consists of two symme- 
trical parts, coming from the back of the head, and inserted into the 
front of it. It is superficial, being placed immediately below the 

* 1 may here mention, once for all, in regard to the muscular system, that 
though the very rigid mode of description adopted by anatomists may lead the 
inexperienced student to infer that there are no departures from a common 
standard, and that one invariable type for the muscles prevails in all human 
beings ; yet there will be found upon actual dissection occasional disagree- 
ments with the best established descriptions, and which it is of some use to 
know. Some of these departures are common enough, others very rare; and 
they consist either in a deficiency or a redundancy of muscles. Wishing not 
to give false ideas of their importance and frequency, and, indeed, fearful 
doing so, they aTe purposely introduced subordinately in notes : many of them 
have been observed by me personally, others are recorded in different medical 
writings, and for the remainder I am indebted to the learned treatises on 
anatomy of T. Soemmering and J. F. Meckel. 

No part of the muscular system varies more in different subjects than the 
muscles of the back ; but, as it would be useless to enter fully on such trivial 
details, they have been passed by, except in a few instances. 

f Anat. Atlas, Fig. 167 to 172 inclusive. 



MUSCLES OF THE NECK. 411 

skin of the scalp, and has four bellies of muscular fibres, two behind 
and two before, connected by a thin tendon, which covers all the 
top of the head. The tendon adheres by a short cellular tissue, 
having no adeps, to the pericranium below, and is attached to the 
common integuments above. This adhesion is made by strong fine 
filaments of fibrous matter, passing in a line, more or less vertical, 
from the under surface of the skin to the tendon of the occipito- 
frontalis. The common integuments on the hairy scalp are formed 
by skin and by a closely adhering, and, indeed, almost inseparable 
layer of granulated adeps, intermixed with the capsules of the hairs, 
and the fibrous filaments alluded to. The thickness of the integu- 
ments thus situated is frequently three lines. 

This muscle arises from the superior semi-circular ridges of the 
os occipitis by tendinous and fleshy fibres, which form two distinct 
bellies (musculus occipitalis) about an inch and a-half long, one on 
each side of the bone. Its tendon, when carefully traced, will be 
found terminating a little jn front of the coronal suture, in the two 
anterior fleshy bellies (musculus frontalis) which cover the whole 
front part of the os frontis. The internal edges of these latter are 
in conjunction below. 

It is inserted, on each side, fleshy, into the superior margin of the 
orbicularis oculi and of the corrugator supercilii ; and, by its nasal 
slip, into the internal angular process of the os frontis, and into the 
root of the os nasi. 

It pulls the skin of the head backwards and forwards, and throws 
that of the forehead into horizontal wrinkles. It also elevates the 
supercilia.* 



Compressor Naris, 

The compressor naris arises by a pointed beginning from the root 
of the ala nasi, and spreads like a fan over the lateral parts of the 
nose below ; it is inserted into its fellow of the opposite side on the 
dorsum of the nose, and into the lower part of the os nasi, where it 
is connected with the nasal slip of the occipito-frontalis. 

This muscle consists of thin and pale fibres placed immediately 
under the skin. If it act from both extremities, by its curved fibres 

* Varieties. Its fleshy portion is said to have covered, in some instances, 
the whole skull-cap. 



412 



MUSCLES. 



being made straight, it will compress the nostril ; but if it act from 
its dorsal margin, assisted by the nasal slip of the occipito-frontalis, 
it will dilate the ala nasi, and has, therefore, been called Dilatans 
Nasi by Columbus. 

The Dilatans nasi posterior of Theile is a thin small plane of mus- 
cle arising from the upper lateral margin of the anterior bony naris, 
and the contiguous cartilage of the nose, and is inserted into the 
ala nasi. It draws the posterior half of the ala nasi backwards and 
dilates the nasal opening. 

Professor Theile informs us that a microscope is required to detect 
its nature. With such qualification, its addition to the anatomical 
description of the face is at least of equivocal utility. 



Orbicularis, or Sphincter Palpebrarum. 

The orbicularis oculi or palpebrarum is a broad circular muscle, 
lying immediately under the skin of the eyelids, and over the tarsi 
cartilages. It is much connected with essential points in the ana- 
tomy of the eyelid. 

Its diameter exceeds that of the orbit, by from four to eight lines 
all around. The fixed point of this muscle is principally the liga- 
mentum palpebrale internum and the internal canthus of the orbit ; 
for, in the greater part of its extent, besides, it is only loosely at- 
tached to the parts below. 

The orbicularis arises, along the whole superior margin of the 
internal palpebral ligament. It also arises, by short tendinous fibres, 
rom the upper end of the nasal process of the os maxillare superius, 
from the internal angular process of the os frontis, and from the con- 
tiguous part of the os unguis. 

The fibres from this origin compose the lamina of the upper eye- 
lid. They may be traced, thence, around to the lower eyelid, and 
are found again terminating at the internal canthus of the orbit, 
where they are fixed into the anterior margin of the orbitar process 
of the upper maxillary bone, into the corresponding ridge of its 
nasal process, and into the inferior margin of the internal palpebral 
ligament from which it arose. 

The temporal portion of this muscle is attached to the temporal 
fascia, so as to prevent it from being much displaced. It is, there- 



MUSCLES OF THE NECK. 413 

fore, obvious that the effect of the contraction of the upper and of 
the lower half of the muscle will be to bring the eyelids together. 
The fulcrum of motion is the internal or nasal side, as manifested by 
the radiated wrinkling of the skin at that point. 

The interior portion of this muscle, which is laid upon the tarsi 
cartilages, is called Ciliaris by Albinus : this distinction, which is 
too arbitrary, is now generally abandoned. 



TJie Corrugator Supercilii. 

This muscle is placed beneath the upper margin of the orbicularis, 
at its internal extremity; by which, and by the adjacent portion of 
the occipito-frontalis, it is concealed. 

It arises from the internal angular process of the os frontis, and 
going outwards and a little upwards, its fibres are lost in the infe^ 
rior margin of the occipito-frontalis and in the superior of the orbi- 
cularis. 

It draws the eyebrow and the skin of the forehead into vertical 
wrinkles, and also draws them over the eye so as to overshadow it. 



The Levator Labii Superioris et Alee Nasi, 

Is fixed just at the side of the nose. It arises by a pointed pro-; 
duction from the nasal process of the superior maxillary bone at the 
internal canthus of the eye, and by a broad origin from the anterior 
margin of the orbitar process of the same bone. Passing downwards, 
it is inserted into the side of the ala nasi, and into the upper lip, 
being narrower below than above. The part of this muscle which 
comes from the orbitar process is so distinct, that Albinus and the 
continental anatomists give it the exclusive name of Levator Labii 
Superioris. 

It draws the upper lip and the ala nasi upwards. 

Just beneath this muscle there is sometimes a fasciculus, called 
the Anomalus Faciei of Albinus, which is attached by one end to 
the os maxillare superius near the canine fossa, and by the other to 
the upper lip. 

35* 



414 



MUSCLES. 



The Levator Anguli Oris, 

Is a small muscle, concealed very much by the last ; it arises from 
the anterior part of the superior maxillary bone, between the fora- 
men infra-orbitarium and the first bicuspate tooth, and is inserted 
into the corner of the mouth. 

It raises the angle of the mouth. 



TJie Zygomaticus Minor, 

Is a small muscle, arising from the fore part of the os make; it 
descends obliquely, and is inserted into the upper lip just above the 
corner of the mouth.* 



Zygomaticus Major, 

Is just on the outside of the last, and is much larger. It arises 
from the malar bone, externally, at its posterior inferior part, just 
above the lower edge, where this bone contributes to form the 
zygoma. It passes obliquely downwards to be inserted into the 
corner of the mouth, and runs into the depressor anguli oris. 

The last two muscles draw the corner of the mouth towards the 
cheek bone, or obliquely upwards and outwards, as in smiling. 



The Depresses' Labii Superioris et Alee, Nasi, 

Is concealed by the orbicularis oris, and the levator labii supe- 
rioris etake nasi. To get a view of it, the upper lip must be in- 
verted, and the lining membrane of the mouth removed on the side 
of the fraenum of the lip. This muscle arises from the inferior part 
of the upper maxilla in front of the alveolar processes for the dens 

* Varieties. Frequently it is deficient; sometimes it is a fasciculus of the 
orbicularis oculi ; sometimes it is double ; sometimes it does not reach the corner 
of the mouth. 



MUSCLES OF THE FACE. 415 

caninus and the incisores, and is inserted into the side of the ala 
nasi, and into the contiguous part of the upper lip. 
It depresses the upper lip and the ala nasi. 



The Depressor Anguli Oris, 

Arises broad and fleshy from the base of the lower jaw on the 
side of the chin; being somewhat triangular, its apex is inserted 
into the corner of the mouth. 

This muscle draws the corner of the mouth downwards. It lies 
immediately under the skin, and blends above with the zygomaticus 
major and with the levator anguli oris. 



The Depressor Labii Inferioris, 

Is in part beneath the last muscle, and, like it, arises broad and 
fleshy from the basis of the lower jaw on the side of the chin; its 
fibres pass obliquely upwards and inwards, and are inserted into 
the whole side of the lower lip. 

It draws the lip downwards. 

These last two muscles are much obscured by being mixed with 
a quantity of adipose matter; the skin, also, is closely blended with 
them, and the roots of the beard penetrate between the intervals of 
their fibres.* 



The Levator Menti, or Labii hiferioris, 

Being placed beneath the depressor labii inferioris, is demon- 
strated by turning downwards the lower lip and dissecting away its 
lining membrane on the side of the fraenum ; it will then be seen to 
arise in front of the alveolar processes of the external incisor and 
the canine tooth, and, passing obliquely downwards, to be inserted 
into the lower lip. 

It elevates the lower lip. 

Varieties. Its exterior border is often formed by the Platysma Myodes. 



416 MUSCLES. 



TJie Buccinator, 

Arises from the root of the coronoid process of the lower maxilla; 
from the back part of the upper maxilla near the pterygoid process 
of the sphenoid bone, and from the roots of the alveolar processes 
of both the upper and the lower maxillary bone, as far forwards as 
the dentes bicuspides. It is inserted into the corner of the mouth, 
and into the contiguous parts of the upper and lower lips. 

It draws the corner of the mouth directly backwards. 



The Orbicularis. Oris, 

Is a circular muscle just beneath the skin, much blended with 
adipose matter externally, but more plain on the surface contiguous 
to the lining membrane of the mouth. It constitutes a considerable 
part of the thickness of the lips, and surrounds the mouth entirely. 
It has no bony origin, but arises from the fibres of the several muscles 
which join each other at the corner of the mouth, and therefore con- 
sists of two semicircular planes, one for the upper and the other for 
the lower lip. 

It is the antagonist to most of the other muscles of the mouth. 
From its superior part a pyramidal slip goes to the tip of the nose, 
being called, by Albinus, Nasalis Labii Superioris. 



Masseter. 

The masseter is placed between the skin and the ramus of the 
lower jaw ; it is of an oblong shape, and evidently consists of two 
portions, an external and an internal, which may be readily recog- 
nised by the course of their fibres as they decussate. 

As a whole, it arises, tendinous and fleshy, from the malar pro- 
cess of the os maxillare superius ; from the inferior edge of the malar 
bone, between the maxillary and the zygomatic sutures, and from 
the zygomatic process of the temporal bone. Of its two portions, the 
internal is the smaller, and is inserted tendinous into the outer part of 
the root of the coronoid process of the lower jaw; while the external 
extends from the malar bone to, the angle and contiguous part of the 



MUSCLES OE THE FACE. 417 

lower jaw, where it is inserted tendinous and fleshy. A part of the 
internal portion may be seen at the zygomatic suture, behind the 
external, without the latter being raised up. 

Both portions have the power to close the jaws : the external, 
also draws the lower jaw forwards ; and the internal, also draws it 
backwards. 



Temporalis. 

The temporal muscle is placed on the side of the head, and oc- 
cupies its middle inferior region. It is covered externally by the 
Fascia Temporalis, a thick, dense, tendinous membrane ; which arises 
by the semicircular ridge on the side of the cranium, and is inserted 
into the upper margin of the zygoma. 

The temporal muscle arises from the inner face of this fascia ; from 
the whole length of the semicircular ridge on the side of the os frontis 
and parietale ; and from the surface of the cranium between this ridge 
and the zygoma, including the part contributed by the frontal bone., 
the parietal, the squamous portion of the temporal, and the sphenoid. 
This muscle also receives an accession of fleshy fibres from the in- 
ternal face of the zygoma. 

From this extensive origin the fibres converge towards the zygo- 
ma, and passing beneath it, are inserted tendinous into the coronoid 
process of the lower jaw, so as to surround it on every side ; some 
of these tendinous fibres go down in front almost to the last dens 
molaris. 

It pulls the lower jaw directly upwards. 



[Pterygoideus Externus* 

The external pterygoid muscle, so called from its position, arises 
fleshy from the outer side of the external pterygoid process of the 
sphenoid bone, and from the adjoining surfaces of the same bone 
by its spinous and temporal processes ; also from the tuber of the 
upper maxillary. 

It passes outwards and backwards horizontally, and is inserted 



418 MUSCLES. 

into the inner side of the neck of the inferior maxilla, and into the 
capsular ligament of the articulation. 

When the muscles of the opposite sides act together, they draw 
the lower jaw forwards, but if alternately, they give it a grinding 
motion,* 

Pterygoideus Internus. 

The Internal Pterygoid muscle arises by tendinous and fleshy 
fibres from the internal pterygoid process of the sphenoid bone, 
along the outer margin of the Eustachian tube, and from the greater 
part of the pterygoid fossa. Passing downwards and backwards, 
it is inserted tendinous and fleshy into the internal face of the angle 
of the lower jaw. 

When the muscles of the opposite sides act, they close the jaw. 



SECT. II. — MUSCLES OF THE NECK.f 
Of the Fascia Superficialis Colli, 

Between the skin of the neck and its superficial muscles, may be 
observed a layer of compact cellular substance, the consistence of 
which is more strongly marked in some subjects than in others. It 
is the continuation of the same membrane which is spread upon the 
external abdominal muscles, and is called there the Fascia Superfi- 
cialis Abdominis. Passing from the abdomen over the thorax, it ad- 
heres to the clavicles and sternum, but not very strongly; it then goes 
from them over the neck to the face, being slightly fastened to the 
base of the lower jaw in advance of the masseter muscle. 

It is spread over the submaxillary and parotid glands, is in many 
subjects strongly marked there by its fibrous character ; and sends 
down partitions between their lobules, as well as between the mus- 
cles and their fasciculi; thereby forming sheaths for the same. By 
these partitions it communicates with the fascia profunda colli. 
Above it is fixed to the mastoid process, to the meatus auditorius 
externus, and to the zygoma. Just above the latter it adheres to the 

* Varieties. I have seen, in one case, this muscle continued into the infe- 
rior margin of the temporal. 

f Anat. Atlas, Figs. 167 to 176, inclusive. 



MUSCLES OF THE NECK. 419 

fascia temporalis, and a thin layer of fat intervenes between them. 
This fascia is more strongly characterized about the parotid gland 
and lower jaw than elsewhere. It is remarkably distinct in the 
foetus at full time, the sheaths, which it forms for the muscles, being 
then very clear of adipose matter, and semi-diaphanous. 



The Platysma Myodes, 

Or the Musculus Cutaneus, lies upon the fascia superficialis, or 
rather is included between two laminae of it, one above and the 
other below, forming its sheath, which is very thin, especially on 
the side next to the skin. This muscle covers, by its breadth, a 
very considerable portion of the side of the neck ; and extends, ob- 
liquely, from the thorax to the face. 

It arises from the condensed cellular membrane on the upper part 
of the pectoralis major muscle, and of the deltoid, just below the 
clavicle, nearly the whole length of this bone. Its fibres are much 
more pale than those of other voluntary muscles, are collected into 
longitudinal fasciculi, constituting a plane of scarcely a line in thick- 
ness, and terminate in the integuments of the lower jaw and cheek. 
It is slightly attached to the lower jaw, and not unfrequently runs 
into the muscles of the low^er part of the face. 

When the whole muscle is in action, it elevates the skin of the 
neck. The external jugular vein is seen running nearly in the 
centre of it, in the same direction with the fibres of this muscle, and 
between it and the sterno-cleido mastoid.* 

Upon the upper part of this muscle there is occasionally a thin 
distinct plane of fibres crossing it and running into the depressor 
anguli oris. This is the Musculus Risorius of Santorini. 



The Sterno-Cleido Mastoideus, 

Is beneath, and decussates the last muscle. It forms always a 
prominent feature in the outline of the neck, in passing obliquely 
from the upper front part of the thorax to the base of the cranium. 

* Varieties. In some rare instances this muscle has been found thick and 
round ; and instead of going towards the face, inserted into the occiput. 



420 MUSCLES. 

It arises tendinous and fleshy from the edge of the upper part of 
the sternum, and fleshy from the sternal end of the clavicle. These 
origins are separated by a considerable fissure ; but they soon unite. 
It is inserted tendinous into the mastoid process, and into the part of 
the superior transverse ridge of the cranium next to it. 

It draws the chin towards the sternum.* 



Of the Fascia Profunda Colli. 

When the origin of the sterno-cleido mastoideus is turned to one 
side, the Fascia Profunda of the neck is seen beneath the fascia 
superficialis, and somewhat separated from it by a lamina of cellular 
adipose matter. This membrane arises from the larynx, forms a 
thin capsule to the thyroid gland, and, being closely attached to its 
inferior margin, descends by investing the sterno-hyoid and thyroid 
muscles, being well seen on their anterior surfaces. It is firmly 
fastened to the upper edge of the sternum, to the sternal end of the 
clavicles, and to the cartilages of the first pair of ribs, forming an 
elastic and resisting membrane from the larynx to the thorax. By 
turning off the sterno-hyoid and thyroid muscles from their attach- 
ment to the sternum, the fascia profunda will be seen still more 
distinctly, passing behind them from the inferior margin of the 
thyroid gland, to the upper bone of the sternum : this lamina of it is 
inserted into the sternum, twelve or fifteen lines below the upper 
edge. It encloses or surrounds the transverse vein and the arteria 
innominata. Beneath the fascia profunda, are the trachea, the roots 
of the arteries of the head and upper extremities and the trunks of 
their veins. There is much loose cellular and adipose matter placed 
at the lower part of the neck, beneath this fascia ; and between it 
and the trachea; through which the thyroid veins with their ramifica- 
tions pass. This last circumstance must always render suppurations 
and operations in the part highly dangerous, as the pus will form 
fistula? under the sternum ; moreover, the continual motion of the 

* Varieties. Sometimes a fasciculus, at its posterior margin, is presented in a 
state entirely insulated. Occasionally, its lower extremity has been observed 
to reach as far as the rectus abdominis muscle, and even to the point of the third 
bone of the sternum. The fissure between the sternal and clavicular portions 
in mammiferous animals, is, naturally, so much extended, as to produce two 
distinct muscles. 



MUSCLES OF THE NECK. 421 

part in respiration, prevents adhesions from forming, and, therefore, 
disposes to ulceration. An ingenious idea on the uses of this fascia 
and of the sterno-hyoid and thyroid muscles as connected with it, 
was suggested by the late Allen Burns : he conceived that they were 
a defence to the upper part of the thorax, and sustained, in inspira- 
tion, the atmospheric pressure, which, without them, would fall upon 
the trachea and produce difficulty of breathing, from the air not 
passing through the larynx rapidly enough to keep pace with the 
dilatation of the thorax. He illustrates the opinion by a case very 
much in point, of a gentleman who had lost this fascia and the 
muscles by suppuration, and who was afterwards incommoded by 
atmospheric pressure upon the trachea at this place.* Mr. Velpeau, 
on the contrary, asserts that cutting through it in opening abscesses 
and in operations has no such consequence. f 

The external borders of the fascia profunda are continued into 
the sheaths of the great vessels of the neck. >Itrand the fascia su- 
perficialis are also continuous with one another along the anterior 
edge of the sterno-cleido mastoideus. ■ 

Within the inferior maxilla, at its angk, ; a ligamentous expansion 
arises at the pterygoideus externus muscle, and is spread out be- 
tween the styloid process, and the ramus of the lower jaw. This 
membrane, described as the stylo-maxillary ligament, is joined at 
its inferior edge by the fascia superficialis, just before the upper 
part of the sterno-mastoideus, and which increases its breadth 
downwards in the neck, giving it somew r hat the condition of a 
vertical septum of that region : at its lower edge it runs into the 
theca of the great vessels of the neck. Through its lower part 
penetrate the stylo-hyoideus and the disgastricus muscle, and the 
upper part separates the parotid from the sub-maxillary gland. It 
is felt like a cord extending downwards and backwards below the 
angle of the maxilla inferior. It is connected at its internal edge 
with the compages of the nerves and vessels of the part, in such a 

* The late Dr. Lawrence informed me that the fascia profunda is well de* 
veloped in the neck of a cat, and that having occasion to remove it in an ex- 
periment, the respiration of the animal was conducted with great difficulty, 
amounting almost to suffocation. This is a good confirmation of Mr. Burns's 
hypothesis. When lymphatic or scirrhous tumours are evolved behind the upper 
end of the sternum, this fascia forces them against the trachea and thus pro- 
duces a distressing impediment to respiration. 

f Anat. Chir. Vol. u p» 438, 2d edit, 
Vol. L— 36 



422 MUSCLES. 

manner as to forbid description, but the practical anatomist will find 
no difficulty in discovering and understanding it. 

Below this septum, the round ligament, like a nerve, passes from 
the extremity of the styloid process to the appendix of the os 
hyoides. 

The fascia profunda colli is also well marked in the foetus, and 
not much blended with adipose matter. It, like the fascia super- 
ficialis, is only a sheath for the muscles which it surrounds, and is 
called fascia from having some development of fibrous matter in its 
substance. 

The Sterno-HyoideuS) 

Arises thin and fleshy on the interior of the thorax from the ap- 
proximated surfaces of the cartilage of the first rib, the clavicle, 
and the first bone of the sternum ; it passes upwards somewhat 
obliquely, and is inserted into the inferior edge of the base of the os 
hyoides. Its lower end is covered by the sterno-mastoideus. 

It draws the os hyoides towards the sternum.* 



The Sterno-Thyroideus, 

Is beneath the last, and concealed, in a considerable degree, by 
it. It arises fleshy from the interior surface of the sternum, about 
an inch below its upper margin, and from the cartilage of the first 
rib; diminishing somewhat in breadth, as it ascends, it is inserted 
obliquely into the side of the thyroid cartilage. 

It draws this cartilage towards the sternum. f 

* Varieties. Sometimes it arises from the middle of the clavicle ; it is 
double, or is confounded below with the next muscle. 

f Varieties. Sometimes there are two of these muscles, one placed above 
the other; sometimes it runs into the inferior constrictor of the pharynx ; some- 
times it runs into the posterior margin of the thyro-hyoid muscle; sometimes 
the muscle on one side is united to the other by transverse fibres. I have, in 
one instance, Jan. 1, 1839, seen a slip at the external margin of this muscle 
which arising from the cartilage of the first rib, ascended in front of the great 
vessels, and was inserted into their sheath on a level with the thyroid 
cartilage. 






MUSCLES OF THE NECK. 423 



The Thyro-Hyoideus, 

Arises obliquely from the side of the Thyroid Cartilage externally, 
and is inserted into a part of the base, and into nearly all the cornu 
of the os hyoides. It seems almost like a continuation of the Sterno- 
Thyroideus. 

Its use is to approximate the os hyoides and the thyroid cartilage, 
in doing which it has the effect of planting the epiglottis against the 
root of the tongue, and of drawing the cricoid and the arytenoid 
cartilages against it, so that the opening of the glottis is protected.* 



The OmO'Hyoideus, 

Passes obliquely across the neck, from the superior edge of the 
scapula to the os hyoides. It is a thin, narrow muscle, divided 
into two bellies, one at each end, by an intermediate tendon; its 
inferior part is concealed by the trapezius muscle; its middle, where 
the tendon exists, crosses the great vessels of the neck, and is 
covered by the sterno-cleido-mastoid muscle; and its upper extre- 
mity is overlapped by the platysma myodes. 

It arises from the scapula just behind the notch in its superior 
costa, and curving somewhat downwards in its course, it is in- 
serted into the lower edge of the base of the os hyoides, next to its 
cornu. 

It draws the os hyoides downwards. f 



The Digastricus, 

Is placed at the upper side of the neck, and passes from the back 
part of the base of the head to the chin. 

It arises principally fleshy from the fossa of the temporal bone at 
the base of the mastoid process; its middle is converted into a 

* Varieties. Its fibres sometimes run into those of the middle constrictor 
of the pharynx; sometimes they arise from the cricoid cartilage; sometimes it 
is continuous with the sterno-thyroideus. 

f Varieties. Sometimes it is double, so that besides the usual insertion, it 
has one into the side of the tongue. 



424 MUSCLES. 

round tendon, which passes through the stylo-hyoideus muscle, and 
is fixed by a ligamentous loop to the cornu of the os hyoides. After 
which another fleshy belly is formed, which is inserted into the 
inside of the base of the maxilla inferior, at the side of its symphy- 
sis. It receives an accession from the base of the os hyoides. 

Its use is to draw the os hyoides upwards when its extremities 
are fixed, and, as Mr. Hunter has pointed out, to throw the head 
backwards, and thereby to open the mouth when the lower jaw is 
fixed upon a body of the same height.* 



The Stylo- Hyoideus, 

Is the more superficial of the three styloid muscles. It arises 
tendinous from the middle and inferior part of the styloid process 
of the temporal bone ; and being perforated, as mentioned by 
the tendon of the digastricus, is inserted tendinous into the cartilagi- 
nous juncture of the base and cornu of the os hyoides. 

It draws the os hyoides upwards and backwards, f 



Tlie Stylo- GlossuSy 

Is within and above the other ; it arises from the upper internal 
part of the styloid process, tendinous and fleshy, and is inserted 
into the side of the root of the tongue, forming a part of its struc- 
ture.:}: 

It draws the tongue backwards. § 



The Stylo-Pharyngeus, 

Is more deeply situated than either of the other two muscles. It 
arises from the inner side of the styloid process near its root, and 

* A common variety in this muscle consists in the mutual adhesion of the 
two anterior bellies belonging' to the opposite sides, showing thereby a marked 
tendency to the quadruped arrangement. 

f Varieties. This muscle is frequently double. 

% See Tongue. 

§ Varieties. J. F. Meckel says that on one occasion he found it double on 
both sides. 






MUSCLES OF THE NECK. 425 

runs into the side of the pharynx between the middle and upper con- 
strictors, opposite the tonsil gland ; it afterwards descends between 
the lining membrane of the pharynx and the middle and the lower 
constrictor, and is inserted into the posterior margin of the thyroid 
cartilage. 

It draws the larynx and pharynx upwards. 



The Mylo-Hyoideus, 

Forms the floor of the mouth and suspends the tongue; it arises 
at the root of the alveolar processes of the lower jaw, from a ridge 
extending from the last dens molaris to the chin. Its fibres converge 
towards a white tendinous line, placed between it and its fellow, and 
reaching from the base of the os hyoides to the chin. This muscle 
is concealed by the anterior belly of the digastricus. When it con- 
tracts, it draws the os hyoides upwards and projects the tongue,* 



The Genio-Hyoideus, 

Is concealed by the last; by turning over the anterior edge of 
which, it is seen. It arises tendinous from the posterior tubercle on 
the inside of the symphysis of the lower jaw ; and, increasing some- 
what in breadth, is inserted into the anterior part of the base of the 
os hyoides. 

It draws the os hyoides upwards and forwards, f 

(For the muscles of the tongue, see Mouth.) 

There are several pairs of muscles, on the front and sides of the 
cervical vertebrae which lie closely upon them.| They are named 
from their situations and shapes. 

* Varieties. Sometimes a part of it is inserted into the middle tendon of 
the digastricus, or is joined with the sterno-hyoideus. 

j- Varieties. Sometimes a distinct fasciculus of this muscle is inserted 
into the greater part of the cornu of the os hyoides. Sometimes there is hut 
one muscle. Rarely it is douhle on both sides. 

% Anat. Atlas, Fig. 185. 

36* 



426 MUSCLES. 



1. Longus Colli. 

The Longus Colli is next to the middle line of the vertebrae. It 
arises from the sides of the bodies of the three superior vertebras 
of the back, and from the anterior edges of the transverse processes 
of the five lower cervical vertebras. Its fibres pass somewhat 
obliquely upwards and inwards to be inserted into the front of the 
bodies of all the cervical vertebras. 

It bends the neck forwards, and to one side.* 



2. Rectus Capitis Anticus Major, 

Is placed on the outside of the last. It arises tendinous and 
fleshy from the fronts of the transverse processes of the third, fourth, 
fifth, and sixth cervical vertebras ; forms a considerable fleshy belly, 
and is inserted into the cuneiform process of the os occipitis, just 
before the condyle. 

It bends the head forwards, f 



3. Rectus Capitis Anticus Minor. 

This is a very small muscle. It arises fleshy from the front of 
the first cervical vertebra near its transverse process, and is inserted 
under the rectus major before the root of the condyloid process of 
the occipital bone. 

It bends the head forwards. 



4. Rectus Capitis Lateralis. 

This is also small, and arises fleshy from the front of the trans- 
verse process of the atlas. It is inserted, tendinous and fleshy, at 

* Varieties. Sometimes a fasciculus from the first or second rib, or from 
the body of the sixth or seventh vertebra of the neck, joins it. 
f Sometimes it also arises from the first and second vertebrae. 



MUSCLES OF THE NECK. 427 

the outside of the condyle of the occipital bone, into the ridge leading 
from it to the mastoid process. 

It pulls the head a little to one side.* 



5. Scalenus Prior, or Anticus. 

The scalenus anticus arises by three distinct tendinous heads 
from the transverse process of the fourth, fifth, and sixth cervical 
vertebra, and is inserted tendinous and fleshy into the upper surface 
of the first rib, just anteriorly to its middle. 



6. Scalenus Medius. 

The scalenus medius arises by distinct tendons from the trans- 
verse processes of all the cervical vertebras, and is inserted tendi- 
nous and fleshy into the upper face of the first rib, in all the space 
from its middle to its tubercle. 



7. Scalenus Posticus. 

The scalenus posticus arises from the transverse process of the 
fifth and sixth cervical vertebra, and is inserted into the upper face 
of the second rib, just beyond its tubercle. 

The last three muscles are concealed by the sterno-cleido mas- 
toideus and the anterior edge of the trapezius. The scalenus pos- 
ticus is best seen in dissecting the muscles of the spine and resembles 
very much one of the class to which Albinus gives the name of 
Levatores Costarum. 

All the Scaleni elevate the ribs and bend the neck to one side. 
They are particularly interesting as connected with the course of 
the large blood vessels and nerves of the upper extremity. f 

* Varieties. Sometimes another muscle arises from the body of the first 
vertebra of the neck. 

f Varieties. Besides the three scaleni which are described, there are fre- 
quently supernumerary muscles or fasciculi. One of these, called the Scalenus 
Minimus Albini, is between the first two, and occasionally appears as a fasci- 
culus of the scalenus anticus, separated from it by one or more of the brachial 




428 MUSCLES. 

CHAPTER II. 
Muscles of the Trnnk. 

SECT. I. MUSCLES ON THE FRONT OF THE THORAX.* 

The Pectoralis Major , 

Is superficial, and forms the large swelling cushion of flesh under 
the skin of the breast. It arises tendinous from the anterior face of 
the first two bones of the sternum, their whole length, fleshy from 
the cartilage of the fifth and sixth rib, and by a fleshy slip from the 
upper part of the tendon of the external oblique muscle. It arises, 
also, fleshy from the interior two-thirds of the clavicle. The clavi- 
cular and sternal portions of the origin are separated by an interval, 
giving the appearance of two muscles. 

The fibres converge, and terminate by a broad, thin tendon, which 
is inserted into a roughness on the exterior edge of the bicipital fossa 
of the os humeri, and into the fascia brachialis, just at the internal 
edge of the deltoid muscle. At this insertion it adheres to the ten- 
don of the latissimus dorsi. The under edge of the muscle, near its 
insertion, is folded inwards and upwards, which gives the rounded 
thick margin to the fore part of the axilla. That part of the broad 
tendon belonging to the clavicular portion is inserted lower down 
than the sternal, which produces a decussation of the fibres of the 
tendon. 

The pectoralis major draws the arm inwards and forwards ; and 
also depresses it when it is raised. f 

nerves; it is sometimes double. Another fasciculus, called the Scalenus 
Lateralis, is between the scalenus medius and posticus ; it comes from the trans- 
verse process of the fourth, fifth, and sixth vertebra, and is inserted into the pos- 
terior part of the first rib. 

* Anat. Atlas, Figs. 129, and 177 to 183, inclusive. 

-j- Varieties. Sometimes a single fasciculus arises from the eighth rib, 
which ascends towards the os humeri, has a tendon in its centre, and finally 
joins with the tendon of the pectoralis minor; — sometimes this muscle detaches 
a small fasciculus to the brachialis internus; — sometimes there is a small 



MUSCLES OF THE NECK. 429 



The Pectoralis Minor, 

Is brought into view by raising the last muscle. It is compara- 
tively small, and somewhat triangular. Arising by thin tendinous 
digitations from the upper edge of the third, fourth, and fifth rib, it 
soon becomes fleshy, and is inserted, by a short flat tendon, into the 
inner facet of the coracoid process of the scapula. 

Its use is to draw the scapula inwards and downwards.* 



The Subclavius, 

Is a small muscle, placed immediately under the clavicle. It 
arises from the cartilage of the first rib, and is inserted into the infe- 
rior face of the clavicle, from near the sternum, to the conoid liga- 
ment, which connects the coracoid process and the clavicle together. 

It draws the clavicle downwards, f 

The Serratus Magnus, or Serratus Major Anticus, 

Is a broad muscle, lying on the sides of the ribs, between them 
and the scapula, and beginning at a line anterior to their middle. 

square plane of muscular fibres on its front surface, decussating the fibres at 
right angles ; — sometimes a fasciculus almost cylindrical proceeds from it 
towards the axilla, and, being changed into a long tendon, is inserted into the 
internal tuberosity of the os humeri. Supernumerary fasciculi are also found 
going from one rib to another, or towards the sternum ; sometimes its tendon 
detaches a fasciculus, which crossing the insertion of the muscle, covers the 
bicipital groove of the os humeri like a bridge, is blended with the tendon of 
the supra-spinatus, and increases the thickness of the capsular ligament of the 
shoulder joint. In a muscular male black subject, it was entirely deficient, 
except the external clavicular half. The pectoralis minor was wholly wanting 
in the same. Deer. 1837. 

* Varieties. Sometimes it sends a fleshy fasciculus to the tendinous origin of 
the coraco-brachialis. Sometimes, below it, there is a third pectoral muscle, 
which arises from the first and second rib, and is inserted into the coracoid pro- 
cess; whereby a striking analogy with birds is established. Another variety 
has also been observed in the existence of a fasciculus, which comes from the 
upper rib, and which, covered by the little pectoral muscle, is inserted into the 
capsular ligament of the scapulo-humeral articulation. 

f Varieties. Sometimes two muscles exist ; a bursa mucosa is formed be- 
tween its tendon and the cartilage of the first rib. 



430 MUSCLES. 

It arises from the nine upper ribs by fleshy digitations, the superior 
one of which seems almost like a distinct muscle ; the five lower are 
connected to the obliquus externus abdominis, the digitations of the 
two muscles inter-locking with each other. The fibres converge, 
and are inserted into the base of the scapula its whole length. 
Its action is to draw the scapula forwards.* 

The hitercostales, 

Fill up the spaces between the ribs. There are two in each 
space, of which the external arises from the transverse process of 
the vertebra, and from the inferior acute edge of the rib above, from 
its head almost to its cartilage, and is inserted into the superior 
rounded edge of the rib below for the same distance, its fibres pass- 
ing obliquely forwards and downwards. The internal intercostal 
arises from the inferior edge of the rib and the costal cartilage above, 
beginning at the sternum, and extends backwards to the angle of 
the rib ; it is inserted into the superior rounded edge of the rib and 
costal cartilage, below, on its inner side, its fibres passing obliquely 
backwards and downwards. 

They draw the ribs together. 

The Triangularis Sterni, 

Is on the posterior or cardiac face of the cartilages of the ribs, and 
arises from the whole length of the cartilago ensiformis at its edge, 
and from the inferior half of the edge of the second bone of the 
sternum. The fibres go obliquely upwards and outwards, to be in- 
serted into the cartilage of the third, fourth, fifth and sixth ribs by 
fleshy and tendinous digitations. 

Its use is to depress the ribs, and, consequently, to diminish the 
cavity of the thorax. 

This muscle is frequently defective or redundant in the number of 
its heads, and is commonly more or less continuous with the trans- 
versalis abdominis ; but occasionally it is so much so, that the two 
seem to make but one muscle, and have, therefore, been called 
Sterno-abdominalis, by Rosenmuller. 

* Varieties. Sometimes, it has ten or eleven origins ; the upper origin is 
deficient; the latter is so distinct that it may pass for a particular muscle; a 
wide gap exists in the middle of the muscle, dividing it into two distinct parts. 



MUSCLES OF THE ABDOMEN. 431 



SECT. II. MUSCLES AND FASCLE OF THE ABDOMEN.* 

Between the most superficial of the abdominal muscles, which is 
the external oblique, and the skin with the subcutaneous fat, is found 
the Fascia Superficialis Abdominis. In lean subjects it is very dis- 
tinct, but in fat ones not so much so, from being blended with adi- 
pose matter. The laminae of it which are next to the muscles, are 
kept, in the latter case, rather more free from fat than the more su- 
perficial. It consists of condensed cellular substance, with very little 
fibrous matter in it, and may be considered as taking its origin on 
the front of the thigh, and extending in front of the abdominal mus- 
cles, as high up as the thorax : indeed, if we are disposed to trace 
it to its whole extent, there is no difficulty in following it over the 
front of the thorax ; thence to the neck, as the fascia superficialis 
colli; and even to the face.f In ordinary cases its desmoid or 
aponeurotic character is very equivocal, but where the parts about 
the groin have been pressed upon and thickened by the irritation of 
hernial protrusion, it is better marked. On the thigh it is blended 
with fat ; and encloses between its laminae the lymphatic glands of 
the groin, and the external pudic vessels given off from the femoral 
artery, immediately below Poupart's ligament. On the tendon of 
the external oblique it is more condensed ; branches of the femoral 
artery are also seen in it there. One longer and larger than the 
others, the Arteria ad cutem abdominis of Haller, winds over Pou- 
part's ligament, and runs upwards somewhat in the line of the epi- 
gastric artery, to be distributed to the skin of the abdomen : the 
division of it will produce sufficient hemorrhage to require attention. 

* Anat. Atlas, Fig. 129 and 179 to 184, inclusive. 

f This statement of origin is to be viewed merely as an anatomical license 
for descriptive purposes ; the most natural line of origin is the whole length of 
the linea alba, and this same line might be considered as going along the front 
of the sternum for the pectoral fascia, and along the middle of the neck for its 
fascia superficialis and profunda. — There is one practical advantage in raising 
this fascia from the side towards the linea alba, that we see better a linear 
close adhesion which it makes with the deep edge of Poupart's ligament, and 
also how the part near the anterior superior spinous process, not forming such 
an adhesion, goes down to the thigh and spreads itself over the whole front of 
the inguinal portion of the femoral fascia. This mode of raising exhibits also, 
more satisfactorily, the close adhesion of this fascia to the linea alba behind, 
and to the same line of the skin before. 



432 MUSCLES. 

On the symphysis pubis and about the external ring the laminae of 
the fascia superficialis are multiplied, and it has more of the character 
of common adipose matter, as in most cases the adeps there is abun- 
dant and forms in both sexes the protuberance called the Mons 
Veneris, or Penil. From the pubes it may be traced as a condensed 
cellular membrane blended with the ligamentum suspensorium along 
the penis to its extremity ; and, according to Mr. Colles, of Dublin, 
matter formed beneath it there, is apt to create fistulous sores on 
this organ. A thin process of this membrane may be traced along 
the spermatic cord, and identified with the tunica vaginalis com- 
munis. This fascia is more loosely connected to the parts beneath 
it on the thigh, near the anterior margin of Poupart's ligament, than 
elsewhere, which disposes femoral hernia to observe that course in 
its increase along the margin itself of Poupart's ligament, it forms a 
close adhesion. 

The fascia Superficialis, under the name of Tunica Abdominalis, 
is well developed in animals with a large and projecting belly, par- 
ticularly in the large ruminantia and the solipedia. It has a yellow- 
ish tinge in them, is very elastic and strong, and well calculated to 
support their viscera.* 

There are five pairs of muscles called abdominal ; to wit, the Ex- 
ternal Oblique ; the Internal Oblique ; the Transverse ; the Straight; 
and the Pyramidal. The first three are flat and broad, and lie in 
layers one upon the other ; the other two are long. 



1. Tlie Obliquus Extemus, 

Arises from the eight inferior ribs by muscular and tendinous digi- 
tations attached near their anterior extremities. The first head is 
covered by a slip from the pectoralis major, the five upper heads 
are interlocked with the origins of the serratus major anticus, and the 
three inferior with those of the latissimus dorsi. The fibres pass 
obliquely downwards, and terminate in a broad thin tendon. This 
tendon extends over the whole front of the abdomen, from the lower 
end of the second bone of the sternum to the symphysis of the 
pubes. 

* Breschet, Thesis sur L'Hernie. Paris, 1819. 



MUSCLES OF THE ABDOMEN. 433 

This muscle is inserted in the whole length of the linea alba ; into 
the anterior half or two-thirds of the crista of the ilium, by muscular 
fibres posteriorly, and tendinous anteriorly ; and, from the anterior 
superior spinous process, the tendon extends to the body and to the 
symphysis of the pubes, forming thereby the ligament of Poupart, or 
the Crural Arch. 

In the middle line of the body, the tendons of the three broad 
muscles, on both sides of the abdomen unite to form the Linea Alba, 
which extends from the sternum to the pubes. From two to three 
inches in the adult, on either side of the linea alba, but more distant 
from it above than below r , is another line, formed by the same 
tendons, which is the Linea Semilunaris. The navel, which origi- 
nally was a hole for the passage of the umbilical vessels, and is com- 
monly depressed into a pit, when the skin is on, appears in the 
dissection of the linea alba as a protuberance composed of a con* 
densed cellular membrane. Just at the navel there is a line crossing 
the linea alba, and extending from one linea semilunaris to the other ; 
at the lower end of the Cartilago-Ensiformis, there is another ; and 
half-way between this and the navel, a third : about half-way be* 
tween the navel and the pubes, is a fourth, but it is generally im- 
perfect. These are the Linese Transversa?, and they are formed by 
tendinous matter in the substance of the recti muscles, connecting 
them to their tendinous sheath in front. 

The most interesting insertion of the tendon of the external ob* 
lique, is the portion constituting Poupart's ligament, or the Crural 
Arch. The latter as it gets to the pubes from the ilium, splits so as 
to leave a hole for the passage of the Spermatic Cord in the male, 
and of the Round Ligament of the Uterus in the female. This open- 
ing is named the External Abdominal Ring. The tendon forming 
its upper boundary is inserted into the symphysis pubis, and into the 
pubes of the opposite side, by fibres which are interwoven with and 
decussate those of its fellow. The tendon forming the lower margin 
of the ring is inserted into the spine of the pubes, and into its crista 
for an inch. The portion inserted into the crista of the pubes is 
Gimbernat's ligament, which it will be readily understood, means 
only a part of the Crural Arch. 

The Ring in the External Oblique is rather triangular than round ; 
its base is formed by the body of the pubes, and its point is at the 
place where the tendon splits. The latter is kept from parting still 
farther by a fasciculus of tendinous fibres, which runs across it. The 

Vol. I. — 37 



434 MUSCLES. 

sides of this opening are called its Columns, and from their situation, 
internal and external, or upper and lower Columns. In the female 
it is oval and scarcely half an inch long. 

There are several small round holes in the tendon of this muscle, 
which afford passage to nerves and to veins. When, by the clear- 
ness of the dissection, the tendon has its characteristic gloss and 
polish, they are very distinct. 

Use. This muscle compresses the viscera of the abdomen and 
brings the pelvis and thorax towards each other.* 

Latterly the attention of anatomists has been directed to a flat 
band of cellulo-fibrous matter called the Ventrier or Belly Band ; 
which arises from the tendon of the external oblique, from the linea 
alba to the linea semilunaris, just above the internal abdominal ring ; 
and passes downwards to be inserted into the fascia femoris over 
the origin of the gracilis. Its outer margin reposes in front of the 
spermatic chord and shoves it outwards as the band goes down- 
wards. f 



TJie Obliquus Internus, 

Lies beneath the last, and its fibres pass in a contrary direction 
to the fibres of the other. It arises tendinous, by the fascia lum- 
borurn, from the three inferior spinous processes of the loins and 
from all those of the sacrum ; tendinous and fleshy, from the whole 
length of the crista of the ilium; and fleshy, from the upper half of 
Poupart's ligament. Though the fibres of this muscle, in general, 
decussate the fibres of the external oblique, all of them do not; for 
the lower are brought gradually to pursue the same direction towards 
the symphysis of the pubes. 

Near the Linea Semilunaris, the muscular fibres cease, and the 
tendon begins. 

It is inserted, by condensed fibrous cellular membrane, into the 

* Varieties. Sometimes a considerable part of its middle and anterior por- 
tion is deficient, a vitiated conformation, to which it is subjected alono- with 
the other abdominal muscles. The inferior part of its tendon is incompletely 
developed by the absence of the superficial fibres which retain together the 
more deeply seated, by which it is weakened and caused to gape by one or 
more large oblong fissures : this variety gives occasion to a form of inguinal 
hernia, differing materially from what is common. 

f Thompson, Anat. Du Bas Ventre. Paris, 1838. 



MUSCLES OF THE ABDOMEN. 435 

cartilage of the seventh, eighth, and ninth rib ; and by flesh into the 
tenth, eleventh, and twelfth. It is inserted also, membranous, into 
the side of the ensiform cartilage, its whole length; and into the 
linea alba, from the sternum to the pubes. 

The tendon of this muscle divides into two lamina?, which enclose 
the rectus muscle, and thereby form a sheath for it; imperfect 
however, at the lower posterior part near the pubes. 

Its use is the same as that of the External Oblique.* 



3. The Transversalis Abdominis, 

Arises from the transverse process of the last dorsal, of the four 
upper lumbar vertebrae, and from the back part of the crista 
of the ilium, all, by the Fascia Lumborum. It also arises, fleshy, 
from the anterior two-thirds of the spine of the ilium, and from the 
exterior half of Poupart's ligament; and tendinous and fleshy alter- 
nately, from the inferior margin of the thorax, formed by the carti- 
lages of the six or seven inferior ribs, at their inner surfaces, where 
they are concerned in the origin of the diaphragm. 

The fleshy part of this muscle occupies about one-third of its 
extent. It is inserted into the side of the ensiform cartilage ; filling 
up the vacancy between it and the cartilage of the sixth and seventh 
rib; and into the linea alba, from the extremity of the sternum to 
the pubes. The Transversalis and the Internal Oblique also form 
below a common tendon, which is inserted for an inch into the 
crista of the pubes, behind the insertion of Gimbernat's Ligament ; 
— into the spine of the pubes; — and into that part of the body of 
the pubes which forms the lower posterior boundary of the external 
abdominal ring. Just above this insertion the common tendon 
alluded to splits into two laminae, terminating in the linea alba; one 
of which goes before and the other behind the pyramidalis muscle, 
so that a shea'h is thus formed for it. 

Use; to compress the contents of the abdomen. f 

* Varieties. It is sometimes defective at its lower part, and on other occa- 
sions redundant. 

j- Varieties. Sometimes transverse tendinous fibres creep across its belly, 
and on other occasions a small transverse muscle is present, which decussates 
the larger, and is inserted into the twelfth rib. 



436 MUSCLES. 



4. The Rectus Abdominis, 

Is seen beneath the tendons of the other muscles on either side 
of the linea alba. Its origin is by a flat tendon of an inch or more 
in breadth from the symphysis pubis and the upper posterior part 
of the body of the pubes. The muscle increases gradually in its 
ascent to the breadth of three or four inches. The tendinous in- 
tersections, confining it to the tendinous sheath in front, are fixed 
at the places mentioned as linea? transversa; ; but, for the most part, 
they do not extend through the muscle. When the origins of the 
Recti are examined from behind, it will be seen that the internal 
edge of one tendon, just above the symphysis pubis, overlaps the 
corresponding part of the other; also, that a small pyramidal liga- 
ment finishes more completely the structure just above the sym- 
physis pubis; this ligament is called by Breschet, the Superior 
Pubic. 

The Rectus is inserted fleshy into the base of the cartilago ensi- 
formis, and into the cartilage of the fifth, sixth, and seventh rib. 

It draws the thorax towards the abdomen.* 



5. The Pyramidalis, 

Is at the lower front part of the rectus, and is about three inches 
long. It arises somewhat thick, tendinous, and fleshy, from the 
upper part of the pubes, from near its spine to the symphysis, be- 
tween the rectus behind, and the insertion of the external oblique 
before. Being fixed in the sheath formed by the splitting of the 
tendon of the transversalis muscle it tapers to a point above, and 
is inserted into the linea alba and internal edge of the rectus, for 
about the upper two-thirds of its own length. 

It strengthens the lower part of the abdomen, f 

* Varieties. Tf there be eight sternal ribs, then this muscle has an addi- 
tional costal insertion. It sometimes sends a fasciculus to the fourth rib; and 
I have seen it ascending over the pectoralis major, to the root of the neck, as 
occurs inmammiferous animals. 

f Varieties. It is frequently defective, but sometimes two, three, or even 
four, are seen on a side. When defective, the rectus or obliquus internus is 
better developed than usual. 



J3 

C?- 1-hlrr 

MUSCLES OF THE ABDOMEN. 437 

At the linea semilunaris the tendon of the internal oblique and r jb\\.,u) 
that of the transversalis unite intimately ; and just beyond this June- 1 
tion the two laminae are formed, which enclose the rectus muscle. 
The anterior lamina is the front layer of the tendon of the internal 
oblique, which, after passing half an inch or an inch, is joined to 
the tendon of the external oblique, goes before the rectus muscle, 
and covers it from origin to insertion. The posterior lamina, made 
by the posterior layer of the tendon of the internal oblique, is united 
already at the linea semilunaris to the tendon of the transversalis ; 
in this manner they pass behind the rectus muscle from the car- 
tilago-ensiformis to a line half-way between the umbilicus and the 
pubes. From this line, downwards, all the tendons go in front of 
the rectus muscle. 

The obliquus externus tendon may be dissected from the com- 
mon tendon of the others, without much difficulty, almost to the 
linea alba. The term insertion, expresses, very imperfectly, the 
manner in which the tendons of these broad muscles all terminate 
in the linea alba from the thorax to the pelvis. It should rather be 
said, that they coalesce there by a general intertexture of their 
fibres. 

The Cremaster, 

Is a muscular sheath to the spermatic cord extending from the ex- 
ternal ring to the testicle, and its origin is commonly attributed ex- 
clusively to the internal oblique, as it is said to be a detachment of 
fibres from it ; but it is also formed by fibres from the lower edge of 
the transversalis muscle. The history of its origin is as follows : in 
the descent of the testicle, the latter has to pass beneath that edge of 
the transversalis and of the internal oblique which is extended from 
the outer portion of Poupart's ligament, to the spine and crista of 
the pubes. As the testicle descends it comes in contact with a fasci- 
culus of these fibres, and takes it along. This constitutes the 
Cremaster muscle, which, in adult life, and in a strong muscular 
subject, is seen descending on the outside of the spermatic cord, 
and spreading over the anterior part of the tunica vaginalis in arches 
with their convexities downwards ; then rising on the inner side of 
the cortT to be inserted into the spine of the pubes.* 

It draws up the testicle. 

* Jul. Cloquet, Anat De L'Homme. Tin's account, though easily verr- 

37* 



438 MUSCLES. 



Fascia Transversals Abdominis. 

The Fascia transversalis is placed immediately behind the trans- 
versalis muscle, between.it and the peritoneum. An opening through 
it, which permits the spermatic cord to pass, is called the Internal 
Abdominal Ring, in order to distinguish it from the opening in the 
tendon of the external oblique, called the External Ring. The in- 
ternal ring is rather nearer to the symphysis pubis than to the spine 
of the ilium. The space between the internal ring and the external 
ring, is about eighteen lines in the adult, and is very properly called 
the Abdominal, Inguinal, or Spermatic Canal, from giving passage 
to the Spermatic cord. 

The anterior side of the canal is formed by the tendon of the ex- 
ternal oblique ; the inferior part, in the erect posture, is formed by 
Gimbernat's ligament; the posterior side is formed by the fascia 
transversalis ; and above, this canal is overhung by the internal 
oblique and the transversalis muscle. The spermatic cord, after 
penetrating the fascia transversalis, does not cross, directly at right 
angles, the inferior edge of the internal oblique and transversalis, 
but it slips under them very obliquely ; its inclination being towards 
the pubes, so that it can be considered as disengaged from the infe- 
rior edge of these muscles, only about the middle of the abdominal 
canal. 

The opening in the Fascia Transversalis, or the Internal Ring, is 
not abrupt and well denned ; but the fascia, where it transmits the 
spermatic cord, is reflected by a thin process, and terminates insen- 
sibly in its cellular substance. At the posterior or ventral face of 
the External Ring, the fascia transversalis is not in contact with the 

fied in some subjects, and especially in such as are muscular, does not appear to be 
applicable to all. It does not agree with Mr. John Hunter^ observations on the 
descent of the testicle ; for he always found, while the latter was still in the loins, 
the cremaster running towards it. Moreover, in the buffalo of America, a 
testicle of which the late Dr. R. Harlan, was obliging enough to furnish me 
with for dissection, I found that the cremaster, though remarkably robust and 
strong, formsnone of those nooses or arches with theirconvoxities downwards, 
hut terminates at the testicle in a tendinous and somewhat abrupt manner. 
Taking all these points into consideration, it may be, that a part of the cre- 
master is formed after the manner indicated by Mr. Hunter, and another part 
after that mentioned by M. Cloquet; or, indeed, cases may cccur, presenting 
exclusively one or the other. 



MUSCLES OF THE ABDOMEN. 439 

cord ; but that part of the tendon of the internal oblique and trans- 
versalis which is inserted into the crista of the pubes, and forms a 
sheath for the pyramidalis muscle, is placed between them, and se- 
cures this opening. 

The peritoneum covers the posterior face of the fascia transversalis, 
and is thrown into a duplicature or falciform process, passing from 
near the middle of the crural arch towards the umbilicus. This du- 
plicature depends upon the round ligament of the bladder, which 
was once the umbilical artery of the fetus. It is broader near the 
pelvis than it is above, has its loose edge turned towards the cavity 
of the abdomen, and ascends near the pubic margin of the Internal 
Ring. The effect of its existence is to divide the posterior face of 
the inguinal region into two shallow fossae ; one next to the ilium, 
and the other next to the pubes. The one next to the ilium con- 
tains the beginning of the internal abdominal ring, which is fre- 
quently marked by a little pouch of peritoneum, going along the 
spermatic cord for a few lines. The fossa on the inner or pubic side 
of the falciform process is just behind the external ring, but sepa- 
rated from it by the fascia transversalis, along with the tendon of the 
lower part of the internal oblique and of the transversalis muscle, 
where it is inserted into the pubes, and forms the sheath of the pyra- 
midalis. The two fossse indicate the points where inguinal herniee 
commence ; the proper inguinal protrusion begins in the external 
fossa, and the ventro-inguinal sometimes in the internal fossa. 

The view of the fascia transversalis from behind is extremely 
satisfactory. For a proper knowledge of this membrane, the pro- 
fession is indebted to the labours of Sir Astley Cooper ; and much 
of the zeal with which the anatomy of hernia has been investigated, 
in latter years, is attributable to him. The fascia transversalis is 
a thin tendinous membrane, most generally ; occasionally it is 
merely condensed cellular membrane. It arises from the internal 
or abdominal edge of Poupart's ligament, and from the crista of the 
pubes just behind the insertion of the common tendon of the internal 
oblique and transversalis muscles, and is extended upwards on the 
posterior face of the transversalis muscle to the thorax. At its 
origin it is attached to the inferior edge of the transversalis and 
internal oblique, particularly the part between the internal ring and 
the symphysis pubis. It is also attached to the exterior margin of 
the rectus- abdominis where it is deprived behind of its sheath, and 
it is then continued to the linea alba, where it runs into its fellow. 



440 MUSCLES. 

The internal abdominal ring, or opening in this fascia, marks it out 
in some measure into two portions, of which that on the iliac side of 
the ring is not so thick as the other, or the one on the pubic side ; 
and both portions are much more tendinous near the crural arch than 
they are higher up. 

Were it not for the important influence of the fascia superficialis 
abdominis and the fascia transversalis upon hernia, and the conse- 
quent necessity of a minute knowledge of them, their description 
might be much curtailed in considering them in their proper light, 
to wit ; as sheaths of the abdominal muscles ; for it is now suffi- 
ciently apparent that the first is contiguous to the external oblique, 
and the second to the transverse muscle. Upon the same principle, 
fasciae might be made of all the laminae of cellular substance inter- 
mediate to the abdominal muscles, but it would be useless.* 

On removing the peritoneum from the iliaeus internus muscles, 
the spermatic vessels are seen to descend from the loins to the in- 
ternal ring, where they are joined by the vas deferens coming from 



* A very elaborate and exact account of the construction of the parts 
concerned in hernia has been presented by Alexander Thomson, M. D., 
under the title of Ouvrage complet sur L'Anatomie du Bas Ventre. Paris, 
1838. The character of this work is not so much inventive as distinguished 
by great minuteness of research, and a different distribution of the matter from 
what is common, together with a most copious supply of new terms in place 
of old ones. Highly creditable as it is to his industry, we can scarcely'do less 
than protest against the latter irregularity, and express oar apprehensions that 
this objection, together with the unusual approaches which he has opened to 
the structure as a substitute for the settled ones, will restrict very much the 
reception of his work, and render it less acceptable to both teacher and student. 
The splitting and invention of fasciae was considered for some time as almost 
exclusively an Anglican malady ; but it appears, also, to have propagated 
itself to Paris in an exasperated form in this production of Mr. Thomson; 
and in that of Mr. Velpeau, (Anatomie Chirurgicale,) both, unquestion- 
ably, works of much merit. The practical anatomist may, however, ask, if all 
of the laminae described as such be fasciae, what has become of the cellular 
substance which formerly entered so largely into the composition of the humaa. 
body 1 Will he not rather find verbal novelties than new discoveries 1 A sound 
anatomical verdict is yet to be given on these points: our own opinion is, that 
anatomy is too staid a science for mere caprices in description and names, and 
that such innovations cannot possibly become oecumenical. The introduction 
of a new name in the place of an old one is the highest act of medical authoriiy, 
and is so seldom sanctioned by general suffrage, that an individual inclining to 
it may well pause, lest, in so doing, he may seal up his own publications, by 
the use of terms too little known to be convenient or desirable. 



MUSCLES OF THE ABDOMEN. 441 

the pelvis. As they engage under the edge of the internal oblique 
muscle, after penetrating the ring, the creraaster muscle is detached 
to spread itself over them. The spermatic cord, thus constructed, 
passes through the abdominal canal in the manner mentioned, ob- 
liquely downwards and inwards; and, emerging from the external 
ring, it descends vertically, lying rather upon the outer column of 
the ring than upon its base. . 

On the posterior face of the fascia transversalis, between it and 
the peritoneum, is the Epigastric Artery. The epigastric arises 
from the external iliac as the latter is about to go under the crural 
arch; it ascends inwardly along the internal margin of the internal 
abdominal ring to the exterior margin of the rectus abdominis 
muscle, which it reaches after a course of two and a-half or three 
inches. The spermatic cord, in getting from the abdomen to the 
abdominal canal, therefore, winds, in part, around the epigastric 
artery; in the first of its course being at the iliac edge of the artery, 
and then in front of it. Two epigastric veins attend the artery, one 
on each of its sides, and end by a common trunk in the external 
iliac vein. 

So much space has been devoted to the description of the parts 
concerned in inguinal hernia, that it might be most prudent to let it 
here cease. A fair desire to be accurate, will, with some at least, 
be an apology for my stating, that in practice it will be found that 
the iliac half of Poupart's ligament is bent down towards the thigh, 
by an adhesion to the iliac and the sartorial fascia at their union — 
that the internal oblique and the transversalis muscle, besides the 
adhesion to Poupart's ligament there ; arise also, from the iliac fas- 
cia just above Poupart's ligament, from the anterior superior spinous 
process, almost to the spermatic cord at the internal ring. The 
fascia transversalis, just above them, adheres in line to the iliac 
fascia and as it approaches the femoral vessels, is connected with 
Poupart's ligament but not before ; as it is previously separated from 
the latter by the whole thickness there of the transversalis and inter- 
nal oblique, at their common origin. The distance of the inferior 
margin of the fascia transversalis from Poupart's ligament, at its 
inferior line, increases more and more from the femoral vessels 
towards the anterior superior spinous process, being at the latter at 
least half an inch ; and it is also kept afterwards, about the same dis- 



442 MUSCLES. 

tance from the crista of the ilium, as it adheres there to the circum- 
ference of the iliac fascia.* 

The anatomical arrangement of the parts concerned in inguinal 
hernia in the female is the same as in the male, except that the 
round ligament of the uterus supplies the place of the spermatic 
cord, and there is no cremaster muscle. 

SECT. III. MUSCLES OF THE UPPER AND POSTERIOR 

PARIETES OF THE ABDOMEN.f 

These muscles are constituted by a single symmetrical one, and 
by four pairs: they can only be seen advantageously by removing 
the abdominal viscera. 



1. The Diaphragm, (Diaphragma,) 

Is a complete, though moveable septum, placed between the tho- 
racic and abdominal cavities; it is extremely concave below and 
convex above, the concavity being occupied by several of the ab- 
dominal viscera. It is in contact above with the pericardium and 
lungs, and below with the liver, spleen, and stomach. 

It is connected with the inferior margin of the thorax on all sides, 
and has for its centre a silvery tendon, resembling in its outline the 
heart of a playing card. This cordiform tendon occupies a consi- 
derable part of the extent of the diaphragm, has its apex next to the 
sternum, and its notch towards the spine; and the muscular part of 
the' diaphragm is inserted all round into its circumference. The 
cordiform tendon is nearly horizontal in the erect posture, its eleva- 
tion being on a line with the lower end of the second bone of the 
sternum. On each side of this tendon some of the muscular fibres 
rise so high upwards before they join it, that they are on a horizontal 
level with the anterior end of the fourth rib. The fasciculi of mus- 
cular fibres are, for the most part, convergent from the circumference 
of the thorax, and are easily separated from one another. 

* For an account of both Inguinal and Femoral Hernia, the reader is referred 
to the United States Dissector, or Lessons in Practical Anatomy, by the pre- 
sent author. Revised Edition, 1846. 

f Anat. Atlas, Figs. 187, 188. 



MUSCLES OF THE PARIETES OF THE ABDOMEN. 443 

In the diaphragm are three remarkable foramina. The first (the 
Foramen (Esophageum) is in the back of the muscle, between the 
spine and the notch of the cordiform tendon, a little to the left of 
the middle line. It gives passage to the oesophagus and the par 
vagum nerves along with it, and is rather a fissure or a long ellip- 
tical foramen made by the separation and reunion of the muscular 
fibres; for, above and below, at each end of the ellipsis, these fibres 
decussate one another in columns. To the right of this foramen, 
and a little above its horizontal level, in the back part of the cordi- 
form tendon, is a very large and patulous foramen for the ascending 
vena cava, (Foramen Quadratum.) Its form is between an irregular 
quadrilateral figure and a circle; its edges are composed of fasciculi 
of tendon rounded off, and are not susceptible of displacement, or 
of alteration in their relative position to each other; by which means 
any impediment to the course of the blood in the ascending cava, 
which might arise from a different arrangement, is obviated. Almost 
in a vertical line below, and about three inches from the foramen 
for the oesophagus, is the third hole, in the diaphragm, which affords 
passage to the aorta, (Hiatus Aorticus.) It is just in front of the 
bodies of the three upper lumbar vertebrae, and is a much longer 
elliptical hole than the oesophageal. Its lowest extremity or pole is 
incomplete, being constituted by the tendinous crura of the dia- 
phragm, and its upper by a decussation of muscular fasciculi arising 
from them. Through it, besides the aorta, pass the Thoracic Duct, 
and the Great Splanchnic Nerve of each side. 

In the horizontal position of either the dead or the living body, 
the right side of the diaphragm ascends higher in the thorax than 
the left ; but the weight of the liver makes it, in the vertical posture, 
descend lower than the other. 

Thus circumstanced, the detailed origin of the Diaphragm is as 
follows: It arises fleshy from the internal face of the upper edge of 
the Xiphoid Cartilage ; from the internal face of the cartilages of the 
seventh, eighth, and ninth ribs; from the osseous extremities of the 
tenth and eleventh, and from both the osseous and cartilaginous 
termination of the twelfth rib. As the line described includes 
almost the whole of a circle, and the fibres all converge to the 
cordiform tendon, they, of course, will pass in different radiated 
directions, and be of different lengths, which it is unnecessary to 
specify. Between the sternal and costal portion on each side, there 
is a triangular fissure filled with fatty cellular tissue, and which 



444 MUSCLES. 

sometimes leaves an opening for hernia. I have seen a case of the 
kind, in which the transverse part of the colon was the subject of 
protrusion into the thorax. It is probable that the great displace- 
ment of the abdominal viscera into the thorax, which sometimes 
occurs, may have a congenital origin in this very fissure, and is 
subsequently, when the parts are accommodated to their unnatural 
situation, thought to be a lusus naturse. The portion just described 
is called the Greater Muscle of the Diaphragm. 

Besides these origins, the diaphragm has several from the vertebrae 
of the loins, constituting its crura; there being four on each side of 
the foramen for the aorta. The first pair, entirely tendinous, comes 
from the front of the body of the third vertebra of the loins, and is 
prevented from being very distinct in its origin, in consequence of 
running into the ligament in front of the bodies of all the vertebra?, 
or the Anterior Vertebral Ligament as it is called. The second 
pair of heads is on the outside of the first, and arises, tendinous, 
from the intervertebral ligament, between the second and third 
vertebra. The third pair of heads arises tendinous from the upper 
part of the lateral face of the second lumbar vertebra. And the 
fourth pair of heads comes also tendinous, from the fore part of the 
root of the transverse process of the second lumbar vertebra. These 
tendinous heads terminate in what is called the Lesser Muscle of 
the Diaphragm, which is inserted into the notch of the cordiform 
tendon. It will now be understood that the aorta passes between 
the two sides of the lesser muscle, and that the oesophagus occupies 
a hole in the upper part of its belly.* 

The origin of the diaphragm is completed between its greater 
and lesser muscle, by a tense ligament, the Ligamentum Arcuatum, 
which passes from the root of the transverse process of the first 
lumbar vertebra to the inferior part of the middle of the twelfth rib; 
with the upper edge of this ligament the diaphragm is connected ; 
and with the lower, the psoas magnus muscle, and the quadratus 
lumborum. At the margin of the other ribs, the diaphragm is con- 
nected with the transversalis abdominis. 

* This origin of the lesser muscle of the diaphragm is given by Albinus, 
but it is difficult to make out fairly; for the most part it would be much more 
correct to say that it arises tendinous, from the first, second, and third vertebra 
in front, and the corresponding intervertebral matter. The heads are generally 
much smaller on one side, the left, than the other. From which cause a large 
fasciculus of muscle passes from the right to the left side in ascending, and se- 
parates the hole for the aorta, from that for the oesophagus. 



MUSCLES OF THE PARIETES OF THE ABDOMEN. 445 

Use. In consequence of the muscular fibres of the diaphragm 
passing in a curved direction from the circumference of the thorax 
to the cordiform tendon; and of those fibres forming a sheet con- 
cave below and convex above, their contraction at the same moment 
enlarges the cavity of the thorax, and has a tendency to diminish 
that of the abdomen, which latter is prevented by the yielding of 
the abdominal muscles. In easy respiration, its contractions and 
relaxations produce alternately the actions of inspiration and of ex- 
piration. Its descent, also, assists in the expulsion of faecal and 
other matters from the abdomen. By the experiments of Bourdon,* 
it appears that it only acts a secondary part in the latter, — that its 
functions are limited to inspiration and the associated actions; but 
that in regard to its power of assisting in the expulsion of the con- 
tents of the abdomen, all that it does is first of all to fill the lungs 
with air, and then the closure of the glottis prevents the air from 
being expelled from the lungs. Common observation in parturition 
shows us, that the expulsive efibrt of the abdominal muscles does 
not take place when inspiration is going on, for the former would 
prevent the latter; but the moment that expiration begins, it is 
arrested by the firm closure of the glottis, and then the abdominal 
muscles contract advantageously. 

The Quadratics Lumhorum, 

Is an oblong muscle, arising from the crista of the ilium, at the 
side of the lumbar vertebra?, by a tendinous and fleshy origin of 
three inches in length. It is inserted into the transverse process of 
each of the lumbar vertebra? and of the last of the back by a short 
tendinous slip : it is also inserted into the lower edge of the last rib 
near its head, beneath the ligamentum arcuatum. 

It bends the loins to one side, and draws clown the last rib. 

It is covered behind by the tendinous origin of the transversalis 
abdominis, which separates it from the sacro-lumbalis and from the 
longissimus dorsi. It may also be seen very well from behind, in 
the dissection of the back.f 

* Recherches sur la Respiration et la Circulation. Paris, 1820. 

\ Varieties. Sometimes a broad tendon from it is inserted into the inferior 
margin of the body of the eleventh vertebra of the back. Sometimes a fasci- 
culus of it touches the margin of the eleventh rib, near its head, and above the 
intercostal vessels. 
Vol. I.— 38 



446 MUSCLES. 



The Psoas Parvus, 

Arises, fleshy, from the contiguous edges of the body of the last 
dorsal and of the first lumbar vertebra at their sides, and from the 
intervertebral ligament. It is at the anterior and internal edge of 
the psoas magnus; has a short belly, and a long tendon by which it 
is inserted into the linea innominata, about half-way between the 
spine of the pubes and the junction of this bone with the ilium. 
The tendon, besides, is expanded into the fascia iliaca. 

Its use seems to be, to draw upwards the sheath of the femoral 
vessels, which is derived from the fascia iliaca, and, consequently, 
to draw upwards the vessels themselves ; which probably dimi- 
nishes the liability to injury from their too great or sudden flexion. 
This muscle is sometimes wanting. 

The Psoas Magnus, 

Arises, fleshy, from the side of the bodies of the last dorsal and 
of the four upper lumbar vertebrae, and from the transverse processes 
of all the lumbar vertebrae. It forms an oblong fleshy cushion on the 
side of the lumbar vertebrse, and constituting the lateral boundary 
of the inlet to the pelvis, it passes out of the pelvis, under Poupart's 
ligament, about its middle. 

It is inserted tendinous, into the back part of the trochanter 
minor of the os femoris, and fleshy for an inch below it. 

It bends the body forwards, or draws the thigh upwards.* 

The Iliacus Interims, 

Occupies the concavity of the ilium, being on the outside of the 
psoas magnus. It arises, fleshy, from the transverse process of the 
last lumbar vertebra ; from the internal margin of the crista of the 
ilium ; from the whole concavity of the latter; from its anterior edge 

* Varieties. Sometimes it is joined by muscular fasciculi from the first, 
second, and even third bone of the sacrum. Sometimes, where it borders on 
the pelvis, there is a small fasciculus, which continues distinct almost to the 
trochanter minor, and then sends its own tendon into the common tendon of the 
iliacus internus and psoas magnus. 



MUSCLES OF THE PARIETES OF THE ABDOMEN. 447 

at and above the anterior inferior spinous process; and from that 
part of the capsule of the hip joint near the latter process. 

This muscle terminates in the tendon of the psoas magnus, just 
above its insertion into the trochanter minor. 

This and the psoas magnus, from having a common tendon, might 
with propriety be considered as only one muscle. Their action is 
the same.* 

Of the Fascia Iliaca, 

The Fascia Iliaca is a tendinous membrane, which lies on the 
iliacus internus and the psoas magnus muscle, and is continued into 
the tendon of the Psoas Parvus. Externally, it is connected to the 
margin of the crista of the ilium ; at the internal edge of the psoas mag- 
nus, it is connected with the brim of the pelvis, and sinks into the cavity 
of the pelvis, being continuous with the Aponeurosis Pelvica ; and 
below, it adheres to the edge of the crural arch, from the anterior 
superior spinous process of the ilium almost to the pubes, and is 
continued under it into the sartorial portion of the fascia femoris. It 
makes a line of adhesion from the anterior superior spinous process 
to the femoral vessels, with the fascia transversalis abdominis. The 
external iliac vessels are upon this fascia, between it and the perito- 
neum : and below them the fascia iliaca goes over that part of the 
pubes which gives origin to the pectineus muscle, and is continous 
with the pectineal fascia, or that which covers the pectineus muscle. 
By introducing the finger or a knife handle into a cut through the 
fascia iliaca, its attachment to the crural arch, and its continuity with 
the fascia pectinea and sartoria will be rendered very obvious. 

The iliac vessels pass beneath the crural arch on the inner margin 
of the psoas magnus muscle, the vein being nearest the pubes and 
the artery at the outer side of the vein. The fascia iliaca being 
blended into the crural arch as far as the vein, may indeed be traced 
to the crista of the pubes : it is so connected with the vessels that 
no opening for hernia exists between them, or indeed in all the 

* Varieties. Sometimes an additional fasciculus arises below the inferior 
anterior spinous process, and descends along the external margin of this 
muscle. This fasciculus varies somewhat in its size at different points, and is 
inserted into the linea aspera below the trochanter minor. In very rare cases, 
the iliacus internus is kept totally distinct from the psoas magnus, from origin 
to insertion. 



448 MUSCLES. 

space from the internal margin of the vein to the spine of the ilium. 
But at the inner side of the vein, between it and Gimbernat's liga- 
ment, an opening appears, called the Crural or Femoral Ring, and 
is the place where femoral hernia commences. This opening is ge- 
nerally occupied by a lymphatic gland, and a lamina of condensed 
but loosely attached cellular substance, continuous with the Aponeu- 
rosis Pelvica. 



SECT. IV. — MUSCLES ON THE POSTERIOR FACE OF 
THE TRUNK.* 

The Trapezius or Cucullaris, 

Is a beautiful broad muscle, immediately under the skin, cover- 
ing the back of the neck and thorax, and extending from the bottom 
of the latter to the top of the former. Its anterior edge, above, is 
parallel with the posterior edge of the sterno-cleido-mastoideus. Its 
posterior edge is joined with that of its fellow, and below, it over- 
laps in part the latissimus dorsi. 

It arises by a tendinous membrane from the posterior or external 
occipital protuberance, and from eight or ten lines, sometimes more 
of the superior semicircular ridge of the occiput. It arises tendi- 
nous also from the five superior spinous processes of the neck through 
the intervention of the ligamentum nuchse, and tendinous directly 
from the two lower spinous processes of the neck, and from all those 
of the back. 

It is inserted fleshy into the external third of the clavicle, tendi- 
nous and fleshy into the inner edge of the acromion process, and 
into all the spine of the scapula. Its fibres having a very extended 
origin must of course converge in getting to these insertions ; the 
upper fibres descend, the lower ascend, and the middle are hori- 
zontal.! 

It draws the scapula towards the spine. 

* Anat. Atlas, Figs. 130, 186, 189 to 192, inclusive. 

f A r arieties. It is sometimes short of the origin described, by from one to 
/our, of the lower spinous precesses of the back. Also the lower fasciculus is 
sometimes disjoined from the rest of the muscle, by a large triangular space. 



MUSCLES OF THE PARIETES OF THE ABDOMEN. 449 

In the cervical portion of these muscles, formed by the origins 
of both united, is an elliptical expanse of tendon, lying over the liga- 
mentum nuchae, and extended on each side. The ligamentum 
nuchas itself, as mentioned elsewhere, is a vertical septum of liga- 
mentous matter, extending from the central line of the occipital 
bone, to the spinous processes of all the vertebra of the neck. At 
its upper part where the spinous processes of the neck are short, 
this septum is very broad, and divides completely the muscles of the 
two sides of the neck. 



The Latissimus Dorsi, 

Is situated under the skin at the lower part of the back, so as to 
cover the whole posterior portion of the latter. It arises by a thin 
tendinous membrane, from the seven inferior spinous processes of 
the back; and by a thick tendinous membrane from all those of the 
loins and sacrum. Its origin also extends in this condition along 
the outer inferior margin of the sacrum, and from the posterior third 
of the spine of the ilium.* Besides which, the latissimus dorsi has 
from the sides of the three or four inferior false ribs, as many fleshy 
heads which are connected with the inferior heads of the obliquus 
externus abdominis. 

From this extended origin the fibres converge, so as to form the 
posterior fold of the axilla; and to terminate in a flat, thick tendon, 
of two inches in breadth, which is inserted into the lower part of 
the posterior ridge of the bicipital groove of the os humeri. The 
upper part of this muscle passes over the inferior angle of the sca- 
pula, and derives a fasciculus of fibres from it. It is there behind 
the teres major, but as it advances it winds around the inferior 
edge of the latter so as to get before it. Afterwards the tendons of 
the two adhere closely, but have a bursa between them at their 
termination. That portion of the tendon of the latissimus which is 
continuous with the lower edge of its fleshy belly becomes upper- 
most by a half spiral turn in the latter; while the upper portion is 
by the same arrangement made lowest. At the place of its inser- 
tion, it is commonly connected to the pectoralis major, by an adhe- 

* This origin frequently is tendinous at the back part of the ilium, and fleshy 
in front. 

38* 



450 MUSCLES. 

sion crossing the bicipital groove at its bottom. The inferior margin 
of its tendon detaches a slip to the brachial fascia, and the superior 
margin another to the smaller tuberosity of the os humeri. 
It draws the os humeri downwards and backwards.* 
That portion of its origin being the tendinous membrane coming 
from the spinous processes of the loins is the fascia lumborum, and 
is common to the latissimus, the internal oblique and the transverse 
muscle of the abdomen, and several other muscles to be men- 
tioned. 

The origin of the two latissimi muscles conjointly makes a beau- 
tiful lozenge-shape expansion occupying its entire spinal region, the 
longest diameter is vertical and just over the spinous processes, the 
lateral diameter extends from one crista of the ilium to the other. 



The Serratus Inferior Posticus. 

The origin of this muscle is inseparably united to that of the la- 
tissimus dorsi by the fascia lumborum, and comes from the two 
inferior spinous processes of the back, and the three superior of the 
loins. 

It is inserted by fleshy digitations into the under edge of the four 
inferior ribs. 

It draws the ribs downwards, and is an antagonist to the dia- 
phragm in some respects, but more particularly to the serratus 
superior posticus. 

The removal of the trapezius brings into view several muscles: 
the most superficial of which are the rhomboid, which, being two 
together, look very much like one. 

* Varieties. Sometimes from its anterior extremity a fleshy or tendinous 
slip is detached in front of the coraco-hrachialis, and is inserted into the pos- 
terior face of the tendon of the pectoralis major. The brachial vessels and 
nerves are liable to compression from this arrangement, which is said to be 
natural to birds and moles. Another variety is where a slip runs from this 
rattsele, adheres to the coraco-brachialis, and is inserted tendinous into the 
eoracoid process of the scapula. 



MUSCLES OF THE BACK. 451 



The Rhomboideus Minor, 

Is above the other. It is a narrow muscle which arises by a thin 
lendon from the three inferior spinous processes of the neck, and, 
passing obliquely downwards, is inserted into the base of the scapula 
opposite the beginning of its spine. 

The Rhomboideus Major, 

Arises, also, by a thin tendon from the last spinous process of the 
neck, and from the four superior of the back, and is inserted into all 
the base of the scapula below its spine. 

These muscles draw the scapula upwards and backwards. 



The Serratus Superior Posticus, 

Arises, by a thin tendon from the three inferior spinous processes 
of the neck, and the two superior of the back, and is inserted into 
the second, third, fourth, and fifth ribs, by tendinous and fleshy 
slips, a little beyond their angles. 

This muscle draws the ribs upwards. 

From the Serratus Superior to the Inferior, is an aponeurotic ex- 
pansion described by Rosenmuller, which connects them together, 
and has induced some anatomists to consider them as but one mus- 
cle. It is thin and diaphanous ; but has the fibrous structure very 
apparent, and running in a transverse direction from the spinous pro- 
cesses to the angles of the ribs. The superior margin of the latis- 
simus dorsi also runs into this fascia, so as to render its own bounds 
somewhat undefined. This fascia, along with the ribs and verte- 
brae, forms that gutter in which are contained the deep-seated mus- 
cles of the back. 

The Levator Scapula, 

Is placed between the posterior edge of the sterno-cleido-mas- 
toideus and the anterior of the trapezius ; its lower end is just above 
the rhomboideus minor. It arises by rounded tendons from the 
three, four, or five, superior transverse processes of the neck, be- 
tween the scaleni muscles and the splenius colli. 



452 MUSCLES. 

It is inserted, fleshy, into that part of the base of the scapula 
above the origin of its spine. As its name expresses, it draws the 
scapula upwards. A good view of this muscle may be obtained in 
the front dissection of the neck.* 



The Splenitis, 

Has its inferior extremity beneath the serratus superior posticus, 
but the principal part of it is covered by the trapezius. It arises 
from the spinous processes of the five inferior cervical, and of the 
four superior dorsal vertebrae. 

It is inserted into the back of the mastoid process and continu- 
ously into a small part of the adjacent portion of the os occipitis, 
also into the transverse processes of the two superior cervical ver- 
tebras. It is customary to consider! the part which goes to the head 
as Splenius Capitis, and the part below as Splenius Colli : the latter, 
in that case, is said to arise from the third and fourth dorsal verte- 
brae. It draws the head and neck backwards. 

Between the spinous processes of the vertebrae and the angles of 
the ribs, on either side, the deep fossa is filled up entirely by mus- 
cles. Some of them are large and powerful, and the most striking 
are the Sacro-Lumbalis and the Longissimus Dorsi. 

The Sacro-Lumbalis and Longissimus Dorsi, 

Have a common origin from the back of the pelvis and of the 
lumbar vertebrae, and extend to the top of the thorax. They arise 
tendinous posteriorly, and fleshy anteriorly, from the posterior sur- 
face of the sacrum by its external margin and spinous processes : 
they arise, also, tendinous, from the spinous processes, and fleshy, 
from the ends of the transverse processes of all the vertebrae of the 
loins ; and principally tendinous from the posterior part of the spine 
of the ilium. The external margin of the belly is fleshy ; and all 
the part nearest to the spine is wholly tendinous below, but, higher 

* Varieties. Sometimes it arises from only two superior transverse pro- 
cesses ; occasionally its fasciculi are separated from the neck to the scapula ; 
or a long one is detached towards the spine, thereby presenting a disposition 
similar to what is met with in the dolphin. 

f Albinus, loc. cit. 



MUSCLES OF THE BACK. 453 

up in the loins, it is so only on the surface. The tendon is very strong, 
and divided into fasciculi, chiefly near the spinous processes of the 
lumbar vertebrae. From the under surface of this common belly, 
two heads, tendinous and fleshy, are inserted into the inferior edge 
of the transverse process of each lumbar vertebra, the smaller near 
its root, and the larger near its extremity. On a level with the 
lower rib, and, indeed, somewhat below it, a fissure occurs in the 
muscle which divides it into its two parts. 

The Longissimus Dorsi is nearest the spine ; it is inserted,, by 
small double tendons, proceeding from its internal surface, into the 
ends of the transverse processes of all the vertebrae of the back, ex- 
cept the first. It also from its outer edge sends long slender tendons 
by which it is inserted into the under edges of all the ribs beyond 
their tubercles, except the two inferior. 

The Sacro Lumbalis is inserted from its outer edge into all the 
ribs at their angles, by long and thin tendons, which are succes- 
sively longer, the higher they are inserted. 

By turning over this muscle towards the ribs, from the other, one 
may see coming from the eight lower ribs, as many slips, which run 
into the under surface of the sacro lumbalis : they are the Musculi 
Accessorii ad Sacro Lumbalem. 

These two muscles keep the spine erect, and draw down the ribs.* 

Tlie Spinalis Dorsi, 

Between the ends of the spinous processes and the edge of the 
longissimus dorsi, is a muscle almost entirely tendinous, and scarcely 
to be distinguished from the latter, both in consequence of its close 
connexion with it, and of its insignificant size. At its lower part, it is 
absolutely a portion of the longissimus, and can be separated from 
it only by a forced division. It is a mere string lying along the 
sides of the spinous processes, and is called, from its origin and in- 
sertion, the Spinalis Dorsi. 

* Varieties. The origin is uniform, but the insertions vary in their num- 
ber. Sometimes, a fasciculus commences by a tendinous beginning from the 
fourth rib, and is inserted into the transverse process of the sixth vertebra of 
the neck ; a fasciculus from the sacro lumbalis joins the fascia extended be- 
tween the two serrati, or reaches to the splenius colli : the two muscles are 
sometimes joined closely by an intermediate fasciculus. 



454 MUSCLES. 

It arises tendinous from the spinous processes of the two superior 
lumbar, and of the three inferior dorsal vertebrae, and is inserted, 
tendinous, into the spinous processes of the nine superior dorsal 
vertebrae, except the first. 

In tends to keep the spine erect. 

The Cervicalis Descendens, 

Is a small muscle placed at the upper portion of the thorax, be- 
tween the insertions of the sacro-lumbalis, and of the longissimus 
dorsi into the upper ribs ; it looks at first, very much like a con- 
tinuation or appendix of the first, running to the cervical vertebrae. 

This muscle arises from the upper edges of the four superior ribs 
by long tendons; it forms a small belly which is inserted by three 
distinct tendons respectively into the transverse process of the fourth, 
fifth, and sixth vertebrae of the neck, between the levator scapulae 
and splenius colli. 

It draws the neck backwards. 



The Transversals Cervicis, 

Is on the inner side of the last, and in contact with it, being 
about the same size, and having very much the same course and 
appearance. It is considered as an appendage to the longissimus 
dorsi. 

It arises from the transverse processes of the five superior dorsal 
vertebrae by distinct tendons, and forms a narrow fleshy belly, which 
is inserted by distinct tendons, also, in the transverse processes 
of the five middle cervical vertebrae. 

It draws the head backwards. 



The Traclielo-MastoideuSj 

Is at the inner side of the last muscle, in contact with it. 

It arises by distinct tendinous heads, from the transverse pro- 
cesses of the three superior vertebrae of the back, and of the five in- 
ferior of the neck; and is inserted, by a thin tendon, into the pos- 
terior edge of the mastoid process immediately within the insertion 
of the splenius capitis. 



MUSCLES OF THE BACK. 455 

The dorsal origins are frequently deficient or irregular. 
It draws the head backwards. 



The ComplexuSj 

A fine large muscle, is situated at the inner face of the trachelo- 
mastoideus, and is readily recognised by showing itself between the 
bellies of the two splenii capitis, just below the occiput. A quantity 
of tendinous matter exists in its middle, which gives it the compli- 
cated appearance from whence its name is derived. 

It arises, by tendinous heads, from the seven superior dorsal, and 
the four inferior cervical vertebra?, by their transverse processes; 
also, by a fleshy slip from the spinous process of the first dorsal. 
It is inserted into the inferior part of the os occipitis, by the surface 
between the upper and lower semicircular ridges, on the outside of 
the vertical ridge which exists in the middle of the bone. 

It draws the head backwards. 



The Semi-spinalis Cervicis, 

Is a muscle which passes obliquely from transverse to spinous 
processes, and is situated between the complexus and the multifidus 
spinse ; the course of its fibres renders it difficult to be distinguished 
from the latter. 

It arises from the transverse processes of the six upper vertebra? 
of the back, by tendons which adhere to those of the adjacent mus- 
cles; and passes up to the neck, to be inserted into the sides of the 
spinous processes of the five middle cervical vertebrae. 

It extends the neck obliquely backwards. 



The Semi-spinalis Dorsi, 

Is lower down on the spine, and with difficulty distinguished 
from the multifidus ; like the last, it passes from transverse to spinous 
processes. It lies under the longissimus dorsi, between it and the 
multifidus. 

This muscle arises by tendons connected with those of the other 
muscles, from the transverse process of the seventh, eighth, ninth, 



456 MUSCLES. 

and tenth dorsal vertebrae ; and passes upwards obliquely, to be in- 
serted, tendinous, into the sides of the spinous processes of the two 
lower cervical, and of the five upper dorsal vertebras. 
It draws the spine obliquely backwards. 



Tlie Multifidus Spina, 

Lies under the muscles as yet mentioned, close to the bones of 
the spine ; in order to see it well, they, therefore, should all be cut 
away. 

It has its commencement, tendinous and fleshy, on the back of 
the sacrum, being connected to its spinous processes and posterior 
surface, also to the back part of the spine of the ilium. It there 
forms a belly, of sufficient magnitude to fill up much of the cavity 
between the spinous processes of the sacrum and the posterior part 
of the ilium. It arises also from the roots of the oblique and trans- 
verse processes of all the vertebras of the loins, of the back, and of 
the four inferior of the neck. 

The multifidus is inserted, tendinous and fleshy, into the roots 
and sides of the spinous processes of all the vertebrae of the loins, 
of the back, and of the five inferior of the neck. 

This muscle consists of a great number of small bellies, which 
are parallel to each other, and each of which arises from a trans- 
verse or oblique process, and goes to the spinous process either of 
the first or second vertebra above it. 

It twists the spine backwards, and keeps it erect. 

Between the head and the first and second vertebra, and be- 
tween the latter two, there are on either side four small muscles, 
intended for the motion of these parts upon each other. They are 
brought into view by the removal of the complexus. 



The Rectus Capitis Posticus Major, 

Arises, tendinous and fleshy, from the extremity of the spinous 
process of the vertebra dentata, and is inserted into the inferior 
transverse or semicircular ridge of the os occipitis, and into a part 
of the continuous surface of bone below it. 



MUSCLES OF THE BACK. 457 

Its shape is pyramidal, the apex being below. It turns the head, 
and also draws it backwards. 



The Rectus Capitus Posticus Minor, 

Is at the internal edge of the first. It arises, tendinous, from the 
tubercle on the back part of the first vertebra, and is inserted into 
the internal end of the inferior transverse or semicircular ridge of the 
os occipitis, and into a part of the surface between it and the fora- 
men magnum. 

It is also pyramidal, with the apex downwards. It draws the 
head backwards. 



The Obliquus Capitis Superior, 

Arises from the transverse process of the first cervical vertebra, 
and is inserted into the outer end of the inferior semicircular ridge 
of the os occipitis, behind the posterior part of the mastoid process, 
and beneath the splenius muscle. 

It draws the head backwards. 



The Obliquus Capitis Inferior, 

Arises from the side of the spinous process of the vertebra den- 
tata, and is inserted into the back part of the transverse process of 
the first vertebra of the neck. 

It rotates the first vertebra on the second. 



The Inter- Spinales, 

Are small short muscles, placed between the spinous processes 
of contiguous vertebrae. In the neck they are double, in conse- 
quence of its spinous processes being bifurcated; in the back they 
are almost entirely tendinous ; in the loins they are single and well 
marked. 

They draw the spinous processes together, and keep the spine 
erect. 

Vol. I.— 39 



458 MUSCLES. 



Tlie Inter- Transversarii, 

Are also short muscles, placed in a similar manner, between the 
transverse processes of the vertebrae. In the neck they are double, 
in the back they are small, tendinous, and not well marked; and in 
the loins they are single and well seen. 

They draw the transverse processes together, and will, of course, 
bend the spine to one side. 



TJie Levatores Costarum, 

Are small muscles concealed by the sacro-lumbalis and longissi- 
mus dorsi, and pass from the transverse processes of the last cervical 
and of the eleven superior dorsal vertebrae, to the upper edges of 
the next ribs. They are twelve on either side of the spine, are ten- 
dinous in their origins and insertions, with intermediate muscular 
bellies. 

The upper ones are small and thin. They increase in magnitude 
as they descend. From the inferior edge of nearly all these muscles 
a fleshy slip is detached, which passes over the rib next below its origin, 
to the second rib below, and occasionally to the third. These slips 
are called Levatores Costarum Longiores. The others which de- 
scend from the transverse process to the rib next below, are called 
Levatores Costarum. Breviores. 

These muscles are parallel in their obliquity, with the external 
intercostals, and are not very obviously separated from them. 
They perform the same service, that of elevating the ribs. 

The Rotatores Dorsi of Professor Theile, of Bern, pass from the 
transverse process of a vertebra below to the under margin of the 
arch of the vertebra above. They are eleven in number on each 
side, beginning at the second dorsal vertebra and ending at the 
twelfth. It may be considered as questionable whether any ad- 
vantage will arise to descriptive anatomy by thus separating from 
the Multifidus Spinae, fasciculi heretofore considered a part of it, 
bat which Professor Theile says are marked off by a layer of cel- 
lular tissue. As much may be said at least of all the numerous 
strips making up the multifidus spinae. 



MUSCLES OF T